Methods for vehicle propulsion

ABSTRACT

A field configurable autonomous vehicle includes modular elements and attachable components. The vehicle can be assembled from these modular elements and components to meet desired mission and performance characteristics without the need to purchase specially designed vehicles for each mission. The vehicle can include a modular propulsion system with magnetic drive.

CROSS REFERENCE TO OTHER PATENT APPLICATIONS

The present application claims the benefit of provisional patentapplication Ser. No. 62/973,045, titled: “Field Configurable UnderwaterAutonomous Vehicle,” filed Sep. 12, 2019 and incorporated herein byreference in its entirety.

The present application claims the benefit of provisional patentapplication Ser. No. 62/974,118, titled: “Magnetic Coupling for UUVSystems,” filed Nov. 13, 2019 and incorporated herein by reference inits entirety.

The present application is a continuation in part and claims the benefitof design application serial number 29/742,034, titled: Marine Vehicle,filed Oct. 3, 2019; the complete disclosure of which is incorporatedherein by reference.

The present application is a continuation in part and claims the benefitof design application serial numbers: 29/742,134 titled “Marine Vehiclewith Shroud;” 29/742/130 titled “Marine Vehicle with Shroud and Lens:”29/742,137 titled “Marine Vehicle with Shroud and Top Lens;” 29/742,129titled “Marine Vehicle with Shroud and Top Continuous Lens;” 29/742,138titled “Marine Vehicle with Shroud and Continuous Lens;” 29/742, 132titled “Marine Vehicle with Lens;” 29/742,135 titled “Marine Vehiclewith Top Lens;” 29/742,133 titled “Marine Vehicle with Continuous TopLens;” and 29/742, 131, titled “Marine Vehicle with Continuous FrontLens; “each filed on Jan. 30, 2020; the complete disclosures of eachwhich are incorporated herein by reference.

The present application is related to the following copending patentapplication serial numbers, each filed the same day herewith: U.S.application Ser. No. 16/974,039 titled “Field Configurable AutonomousVehicle”; U.S. application Ser. No. 16/974,049 titled “FieldConfigurable Spherical Underwater Vehicle”; U.S. application Ser. No.16/974,043 titled “Apparatus and Method for Joining Modules in a FieldConfigurable Vehicle”; U.S. application Ser. No. 16/974,045 titled“Method and Apparatus for Coupling and Positioning Elements on aConfigurable Vehicle”; U.S. application Ser. No. 16/974,042 titled“Method and Apparatus for Transporting Ballast or Cargo in an AutonomousVehicle”; U.S. application Ser. No. 16/974,040 titled “System andApparatus for Attaching and Transporting an Autonomous Vehicle”; U.S.application Ser. No. 16/974,047 titled “Method for Parasitic Transportof an Autonomous Vehicle”; U.S. application Ser. No. 16/974,046 titled“Method and Apparatus for Positioning the Center of Mass on aConfigurable Device”; U.S. application Ser. No. 16/974,048 titled“Buoyancy Control Module for Field Configurable Autonomous Vehicle”;U.S. application Ser. No. 16/974,054 titled “Optical Communications forAutonomous Vehicles”; and U.S. application Ser. No. 16/974,041 titled“Scuttle Module for Field Configurable Vehicle”; the completedisclosures of each which are incorporated herein by reference.

STATEMENT OF GOVERNMENT INTEREST

The invention described herein may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

BACKGROUND OF THE INVENTION

Unmanned Undersea Vehicles (UUVs) and other unmanned and autonomousvehicles are highly specialized, specially configured vehicles. Theirconfiguration, payload and propulsion, as well as other attributes, aredesigned specifically for a single or very narrow range of missions.This fact results in the expenditure of significant nonrecurringengineering and development costs to make and manufacture each specialpurpose vehicle. These factors contribute to the cost of existingunmanned vehicles and UUVs making them especially expensive to produceand acquire.

Such specially designed vehicles also have very narrowly defined typesof use and utility. This narrow range of uses, correspondingly limitsthe addressable market or numbers of potential purchasers, foreclosingopportunities to produce at numbers large enough to take advantage ofeconomies of scale. The narrow range of uses for each vehicle is thus anadditional factor in driving up the cost of production.

The weight, mass, drag, center of gravity, center of buoyancy, size andlocation of the control surfaces, as well as propulsion and electricalrequirements for existing vehicles are fixed at time of vehicle designand manufacture. The vehicle cannot be modified in the field aftermanufacture. Expanding, altering, or changing the vehicle design to meeta wider or new range of customer needs requires redesigning,reconfiguring and re-manufacturing a completely new vehicle. Thus, UUVand unmanned vehicle designs and their missions remain fairly fixed onceproduced, devoid of new innovations and new capabilities.

The mission specific nature of the designs also drives operator costsand limits operator mission flexibility. To perform a different missionother than the one originally intended requires the purchase of anothervehicle designed for that purpose. Operators often purchase a quiver ofexpensive UUVs to ensure that there is at least one UUV on hand capableof meeting the current mission requirements. For operations without suchaccommodating budgets, vehicle design often limits scope or curtails theability to adapt the mission to changing conditions.

Specialized UUVs and autonomous vehicles often also include proprietarydata busses, communications systems, and interfaces. These proprietarysystems mean that components cannot be shared between vehicles and thata part from one vehicle cannot be used to repair another. Theseproprietary systems also mean that operators must expend time andresources to master the different communications protocols and systemsarchitectures of each vehicle in their inventory; and to adoptspecialized operating procedures and protocols.

The fixed nature of the vehicle design, especially but not limited to,factory sealed and enclosed UUV designs, means breakdowns in the fieldcan often end an entire mission. Once a vehicle component or subsystemfails, the likelihood that it can be repaired or replaced in the fieldis very small. Malfunctions in the field can therefore end a mission orevolution. This situation can be very costly for the operator andintroduce new hazards into a mission. By way of example, if a UUV wereemployed to survey an offshore oil and gas rig and that UUV failed:personnel and equipment must be retrieved, a replacement UUV procured,and the personnel and equipment redeployed. Not only does such aduplicate evolution incur additional time and labor, but in a hazardousenvironment, the duplicative effort exposes additional unnecessary risksto personnel and equipment.

SUMMARY OF THE INVENTION

The present invention includes recognition of the problems andlimitations of prior art UUVs and autonomous vehicles.

According to one aspect of the invention, the invention includes a UUVor autonomous vehicle of modular design. The modules can be assembled inthe factory or in the field without special training or tools. Users canassemble the UUV or vehicle they want, when they need it. The modulardesign enables the vehicle to be assembled by the user to meet theuser's mission parameters and performance goals without the need topurchase individual, separate, mission-specific, vehicles for eachoperation. The modular design additionally enables operators to replacea failed component in the field.

According to another aspect of the invention the configurable, modularUUV or vehicle includes modules and elements of various capabilities andfunctions. These modules can include but are not limited to: command andcontrol, propulsion, control surfaces, maneuvering thrusters,propellers, sensors, power or batter supply units, mass configuration,buoyancy control, legs and footings, ballast, attachment and grapplingmechanisms, payload, communications, antennas, scuttle capability,navigation, and other mechanisms. Modules and elements can be combinedtogether as desired to configure the vehicle as wished.

According to another aspect of the invention, the module's mass, drag,center of gravity or other pertinent characteristics and parameters areprogrammed into each module. When the module is assembled into thevehicle, this information is communicated to the vehicle's command andcontrol system, which then computes or stores the completed vehicle'sstability and control parameters and other configuration data. Thevehicle can also empirically determine its stability and controlcoefficients and control laws.

According to yet another aspect of the invention, each module isindividually sealed to maintain environmental integrity free ofcontaminants or suitability for use under water. Each module cantherefore be separated and replaced without compromising the water-tightnature of the modules and of the vehicle as whole.

According to a further aspect of the invention, the vehicle's electricaldistribution system and data and control busses are integrated withinthe hull of each module. Connectors at the end of each module enable thebusses to be connected to adjacent modules when the modules areassembled together. Modules can optionally perform internal self-checks,once coupled to power via these connections and then provide a visualindication to the operator that a proper connection has been made andthat the module systems are functional. In one possible embodiment ofthe invention, each module incudes an LED for this purpose.

According to a still further aspect of the invention, certain modularcomponents of the vehicle can be attached to and secured, or detachedand released from the vehicle via magnets. In an additional embodiment,magnets can be included as a drive component in the propulsion system.

Using magnets to attach modular components to the vehicle in this mannereliminates the hull penetrations necessary in prior art devices; andwhich can permit ingress of water or other contamination into thevehicle. These prior art hull penetrations are themselves, often asource of failure and routinely incur much maintenance time and expense.In severe cases, failure of the hull penetration can result in loss ofthe entire vehicle. The magnetic attachment of the present inventionthus additionally contributes to the lower cost, low maintenance,greater reliability, and increased productivity of a vehicle accordingto embodiments of the present invention.

In still another embodiment of the invention, magnets can be used tosecure the vehicle to another device such as, for example, an oil rig, amother ship, or buoy. Energizing or engaging this type of attachmentmagnet can be utilized to anchor or station the vehicle at a fixedlocation or device. Such a capability can be employed to navigate to aknown structure or vessel to retrieve the vehicle; or to station keepand collect data before being released to return to after missioncompletion. Such a capability is also useful to attach the vehicle to aferry vehicle for transport to the deployment area. This feature reducesthe battery and power requirements of the vehicle and also permitstransport to areas that would otherwise be inaccessible or beyond theendurance range of the vehicle.

According to yet another aspect of the invention, the hull and modularcomponents of the vehicle may be manufactured using additivemanufacturing or 3D printing techniques, or via injection molding. Thisfeature of the invention reduces costs over traditionally machinedcomponents and additionally allows complex vehicle, module, and elementshapes to be easily fabricated.

Further advantages and features of the present invention will bedescribed in detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1D illustrate several embodiments of a field configurableautonomous vehicle according to the invention;

FIGS. 2A-2D illustrate alternative embodiments of a field configurableautonomous vehicle according to the invention;

FIGS. 3A-3B illustrate other alternative embodiments of a fieldconfigurable autonomous vehicle according to the invention wherein thevehicle is an airborne vehicle;

FIGS. 4A-4B illustrate yet another alternative embodiment of a fieldconfigurable autonomous vehicle according to embodiments of theinvention wherein the vehicle comprises a surface vehicle such as anautonomous toy truck or a boat;

FIGS. 5A-5F are views of module and element joining systems according toembodiments of the invention;

FIGS. 6A-6D is an illustration of axially and diametrically magnetizedmagnets and their operation according to embodiments of the invention;

FIG. 7 is a cross sectional view of a mechanism for attaching fixedexternal configurable elements to a configurable autonomous vehicleaccording to an embodiment of the invention;

FIG. 8 is a cross sectional view of a mechanism for attaching anddetaching releasable external configurable elements to/from aconfigurable autonomous vehicle according to an embodiment of theinvention;

FIG. 9 is cross section of coil spring releasing mechanism according toan embodiment of the invention;

FIG. 10 is a perspective and cross sectional views of a mechanism forattaching and releasing a configurable element from a configurableautonomous vehicle according to an alternative embodiment of theinvention;

FIGS. 11A-11F illustrate parasitic transport and station keeping of afield configurable vehicle according to embodiments of the invention;

FIG. 12 is a cross sectional view of a mechanism for coupling a moveableelement or control surface to a configurable autonomous vehicleaccording to an embodiment of the invention;

FIGS. 13A-13C are side end, and cross sectional views respectively of apropulsion module according to an embodiment of the invention;

FIG. 13D is a cross sectional view of a propulsion module according toan alternative embodiment of the invention;

FIGS. 14A and 14B are illustrations of a counter rotating propellerassembly according to an embodiment of the invention;

FIGS. 15A and 15B are cross sectional views of embodiments of a scuttlemodule according to embodiments of the invention;

FIG. 16 is a systems block diagram of a configurable autonomous vehicleaccording to an embodiment of the invention;

FIG. 17 is a block diagram of a vehicle software architecture accordingto an embodiment of the present invention;

FIG. 18 is a graphical user interface for configuring an autonomousvehicle according to an embodiment on the invention;

FIG. 19 is a block diagram of a fully coupled, fully activated 6 degreeof freedom adaptive plant model control system according to anembodiment of the present invention;

FIGS. 20A and 20B are views of a module for positioning a center of massof a vehicle according to an embodiment of the invention;

FIG. 21 is a cross sectional view of a buoyancy module for positioning acenter of buoyancy of a vehicle according to an embodiment of theinvention;

FIGS. 22A and 22B are a perspective view and a cross sectional viewrespectively of a light communications module or element according to anembodiment of the invention;

FIG. 23 is a light communications system according to an embodiment ofthe invention;

FIG. 24 is a flow chart illustrating use of the present invention;

FIG. 25A is a side view of an initial assembly of an example vehicleaccording to an embodiment of the invention; and

FIG. 25B is a side view of a final configuration of an example vehicleaccording to an embodiment of the invention.

DESCRIPTION OF THE INVENTION

Solely for the convenience of the reader, the Description has beensubdivided into headings and subheadings. These headings and subheadingsdo not limit the metes and bounds of the invention as claimed. TheDescription headings are organized as follows:

1.0 Vehicle Overview and Configurable Components

1.1 Module Fabrication and Field Joints for Connecting Modules andElements

1.2 Module Data Bus and Electrical Distribution System

1.3 Magnets for Modular External Elements, Transit, and Drive Systems

1.3.1 Overview of Magnets and Diametric Magnet Principles

1.3.2 Mounting Fixed External Configurable Elements to Modules

1.3.3 Mounting Detachable Elements to Modules

1.3.4 Payload and Ballast Modules

1.3.5 Parasitic Ferry Transfer and Parasitic Station Keeping

1.3.6 Mounting Moveable External Configurable Elements To Modules

1.3.7 Propulsion Module and Propulsion Systems

1.4 Vehicle Scuttle Module

2.0 Vehicle Systems

2.1 Hardware Systems Architecture

2.2 Software and Logic Systems Architecture

2.3 Vehicle Stability and Control

2.3.1 Dynamically Determined Stability and Control Logic

2.3.2 Center of Mass Redistribution Module

2.3.3 Buoyancy Control Module

2.4 Telemetry and External Communications Systems

2.4.1 Optical Communications Module

2.4.2 Vehicle Swarm Communications

3.0 Example of Use

1.0 Vehicle Overview and Configurable Components

FIGS. 1A-1D show several embodiments of a field configurable vehicle 100according to the present invention. In the embodiment of FIG. 1 ,vehicles 100 are shown as a UUV, but vehicle 100 may comprise other usesand vehicle types, such as, for example, drones, helicopter drones,unmanned autonomous aircraft (UAS), toys, or other autonomous vehiclesand devices. In the embodiment of FIG. 1A, vehicle 100 comprises a firstmodular section 102, paired with a second modular section 104. Frontsection 102 mates with rear section 104 using any of a variety of fieldjoints. According to a preferred embodiment of the invention, section102 mates mechanically and electrically using the mating systemdescribed further below.

Bus 105 electronically couples modules 102 with module 104. Bus 105 canbe used for a variety of functions. In a simple embodiment, bus 105routes electrical power throughout the vehicle. In more elaborateembodiments, bus 105 may further comprise multiple buses including databuses 106 and 107 in addition to power distribution bus 105. Data busescan be used to route command and control signals throughout the vehicleto operate the propulsion system, sensors, store and operate on data, oroperate other subcomponents as desired. Power and data buses and theirphysical and logical architectures are well known to those of skill inthe art. Additional details of one possible bus configuration isdescribed in subsequent sections below.

FIGS. 1B-1D illustrate the additionally modularity and configurabilityof the present invention. In FIG. 1B, vehicle 100 comprises threemodular sections 108, 109, 110. In the embodiment of FIG. 1B, modularsection 108 may comprise any one of a number of types of modules havemultiple purposes or attributes. For example, module 108 may comprise apayload module useful for transporting and delivering a cargo from onelocation to another. Module 108 may also include other additionalhardware and attributes having multiple features and capabilities. Forexample, module 108 can include a temperature or imaging sensor systemin addition to a cargo delivery capability. Module 108 pairsmechanically and electrically with modules 109 and 110 in the samemanner as described in connection with FIG. 1A.

FIG. 1C further illustrates the modularity and field configurable natureof the invention. In the embodiment of FIG. 1C, vehicle 100 can comprisea plurality of modules 108, each with unique and separate capabilities,or alternatively with duplicate functions and purposes.

FIG. 1D shows that in addition to discrete modules 108, various controlsurfaces 120, 122, and 124, propulsion mechanisms 130 and other externalattachments may be attached to configure vehicle 100. In FIG. 1D,control surface 122 comprises a sail plane and control surface 120comprises a stabilizer. Control surfaces 122 and 120, as is known tothose of skill in the art, orient the vehicle in pitch, roll and yaw.Different types of control surfaces beyond those shown in FIG. 1D,including but not limited to, rudders, elevators, bow planes, andcanards may also be attached or detached to reconfigure vehicle 100 asdesired.

FIGS. 2A-2D illustrate alternative embodiments of field configurableautonomous vehicles 200 and 250 according to the invention. In theembodiments of FIGS. 2A-2D, the field configurable vehicle is a UUVcomprising a sphere 201. The UUV of FIGS. 2A-2D may be configured usingthe apparatus and methods of the present invention by adding or removingmodular devices such as different propellers 210, or different thrusters220, different control surfaces 230, or different sensors andcommunications packages 240.

In the field configurable UUVs of FIGS. 2A-2D, thrusters 220 which mayinclude propellers 242 are oriented as shown in FIG. 2C. The vector lineof action 244 of each thruster 220 is thus preferably orthogonal to eachother and pass through the center of gravity of UUV 200. In a preferredembodiment of the invention, the mass distribution of UUV 200 isdesigned such that the center of gravity, and center of buoyancy, iscollocated with the center of sphere 201. UUV 200 is also according toembodiments of the invention, designed to be slightly positivelybuoyant.

The vector line of action of propeller 210 is also preferably throughthe center of gravity of UUV 200. Changing the speed of any ofindividual propeller 242 or 210 results in a thrust vector that canreposition or assist in station keeping UUV 200 without the introductionof significant unwanted moments about the vehicle's axes that must bethen counteracted by the vehicle's control systems/surfaces to maintainvehicle attitude and orientation. This fact results in significanttranslational motion flexibility and minimizes off axis torques which,if present, would need to be counteracted by the vehicle's controlsystems, with corresponding adverse impact on vehicle performance,handling, and endurance.

The UUV 200 of FIGS. 2A, 2B, additionally includes shrouds 246 and 248surrounding propellers 210 and 242 respectively. Shrouds 246 and 248serve as a safety mechanism to prevent hands or clothing from beingcaught in a moving propeller. Shrouds 246 and 248 also protect thepropellers from collision damage and deflect debris or plant life thatmay be in the water column. Shrouds 246 and 248 additionally help directflow axially. A series of openings 249 surrounding each propellerassembly allow fluid moved by each of propellers 210 and 242 to escapepast the vehicle.

FIG. 2D illustrates an alternative spherical UUV 250 wherein UUV 250additionally includes an extended shroud 260 and counter-rotatingpropeller assembly 270. Counter rotating propeller assembly 270 may alsobe constructed according to the teachings of the present invention asdescribed more fully below. Counter rotating propeller assembly 270minimizes roll torque imposed on the vehicle by the rotating motion ofthe propellers. Extended shroud 260 may additionally include internalvanes that separate out and direct the wash from the multiple propellersto prevent the propellers from interfering with each other.

FIGS. 3A-3B illustrate other alternative embodiments of a fieldconfigurable autonomous vehicle according to the invention wherein thevehicle is an airborne vehicle. In the invention of FIG. 3A, a fieldconfigurable autonomous aircraft 300 may be assembled from two or moremodular units 310, 312 and 314 in the same manner previously describedin connection with FIGS. 1A-1D. The aircraft of FIG. 3A may also beconfigured according the inventive methods and apparatus describedherein by attaching modular control surfaces such as, for example: acanard 320; a horizontal stabilizer 340 with elevators 350; a verticaltail 360 with rudder 365; one of a selection of wings 380, and apropulsion module or system propeller 385.

FIG. 3B shows an airborne modular vehicle 390 constructed according tothe present invention wherein the airborne modular vehicle 390 comprisesa helicopter-type drone. Drone 390 may be modularly configured by, forexample, attaching different shapes of rotating propellers 392, addingor removing different footings or landing gear 393, adding or adding orremoving different sensor packages 394, or adding or removing payload orballast modules 396. As will be clear to those of ordinary skill in theart, the modular concepts of the present invention can apply equally toother types of airborne vehicles such as model aircraft, lighter thanair (LTA) airborne vehicles such as blimps, dirigibles, and controllableballoons, as well to radio controlled UAS vehicles, and toys.

FIGS. 4A-4B illustrate yet another alternative embodiment of a fieldconfigurable autonomous vehicle according to embodiments of theinvention wherein the vehicle comprises a surface vehicle such as anautonomous boat 400 or a toy truck 410. Surface vehicles 400 and 410 maybe configured as desired by attaching and removing payloads 420,propellers 440, power pack 450 or other modular items in a manner asdescribed previously in connection with FIGS. 1-3 above.

Solely for ease of discussion, the various modular components andvehicle subsystems shall now be further described with reference tovehicle 100 of FIGS. 1A-1D. The principles, methods, and apparatusdescribed below also apply to any field configurable autonomous vehicleincluding, but not limited to, those described in FIGS. 2-4 .

1.1 Module Fabrication and Field Joints for Connecting Modules andElements

Module hulls may be fabricated from a variety of materials, such as, forexample, metals, composites, or plastics; using a variety of techniquesknown to those of skill in the art, such as machining, molding, casting.In a preferred embodiment of the invention, modules can be fabricatedusing additive manufacturing techniques, such as, for example, 3Dprinting. When modules are formed of composite materials, modules can bespun on a drum or spindle in a manner used in the textile industry orsimilar to that used in the aerospace industry to make the compositehull of the B787 aircraft. When modules are intended for use as a UUV orin other applications that may include exposure to water, modules areformed from non-porous materials or other materials designed to preventthe penetration of water past the hull to the interior of vehicle 100.

In one embodiment of the invention, module hulls are manufactured usingadditive manufacturing techniques known to those of skill in the art.The modules are made of PA-12 nylon, the complete specification of whichis incorporated herein by reference; and are formed in two longitudinalhalves with closed ends having a mechanism for joining with othermodules. Prior to assembling the halves together, the internalcomponents of each module can be placed or secured in the interior; andthen the halves joined together to make the model. The halves may bejoined mechanically or via heat soldering or adhesives using techniquesknown to those of skill in the art.

Modules initially manufactured with open ends can be sealed at each endto protect interior components from damage and from ingress of dirt,grime and water. In one embodiment of the invention, the module isadditionally filled with an engineered fluid for heat transfer such asNOVAC manufactured by 3M. The engineered fluid manages heat fromelectronics contained within the module and maintains the interiortemperature of the module within a desired range to guard against damageto the electronics. The fluid may be injected into the module after itsmanufacture via an injection port which is then sealed closed. Accordingto an additional embodiment of the invention, modules and elementsmanufactured using additive manufacturing techniques can be formed withcapillaries in the hull wall structure. The capillaries are in fluidcommunication with the engineered fluid or may themselves contain theengineered fluid. The system of capillaries transfers heat from theinterior of vehicle 100 to the exterior of vehicle 100. Optionallythermal management of each component module may be accomplished byincluding heat sinks, such as metal strips, in lieu of or in addition touse of engineered fluids.

When vehicle 100 comprises a UUV manufactured from HP-12 nylon, the wallthickness of the hull must be sufficient to withstand pressure at thevehicle's maximum operating depth. According to one embodiment of theinvention, a wall thickness of 5.5 mm enables operation of UUV 200 atdepths of 200 m with adequate safety factors. Exact specifications aredependent upon the water density and the safety factors chosen, as wellas the forces exerted upon the vehicle during vehicle manoeuvres. Sizingof the hull wall thickness depending upon the material properties,operating environment, and mission parameters of vehicle 100 is wellknown to those of skill in the art.

FIGS. 5A-5F show enlargements of a module joining system according to anembodiment of the invention. As shown in FIG. 5A, each module includes amale connection 500 on a first end and a female connection 510 on asecond end. Male connection 500 further includes pins 520 that slideinto corresponding slots 530 in female connection 510. To secure module108 to another module, male connection 500 slides into the femaleconnection of the adjacent module and module 108 is rotated untilapproximately ninety degrees until pins 520 lock in place. Sealinggasket 540 prevents water from entering between the joint. Pressing themodules slightly together as they are joined helps to seal sealinggasket 540. As shown in FIG. 5A, female end 510 of module 108 wouldsimilarly mate to the male end of an additional module in the mannerdescribed above.

FIG. 5B illustrates an end view of the female portion 510 of the joiningsystem of FIG. 5A. In FIG. 5B, module electrical connection points arelocated at 0°(top dead center); 90°; 180°; and 270°. The positive leadof power bus 105 is located at the 90° point. The negative lead of powerbus 105 is located at the 270° connection point. According to onepossible embodiment of the invention, a connection point of solidmaterial assists with maintaining the strength and rigidity of the hull,and can include pogo-type connectors as shown in FIG. 5A.

FIG. 5C shows an end view of male connector 500. On male connector 500the CAN bus lead is located at an orientation 90° to the correspondingCAN bus lead on female connector 510. As the modules join and aretwisted and locked into place, the CAN bus leads on male connector 500and female connector 510 align, making the data bus and power busconnections between modules. An optional light emitting diode (LED) 511can be coupled to power bus 105 and included with each configurablemodule or element. LED 511 can be included on a single end or on bothmale and female ends 500 and 510 as shown. When power is present onpower bus 105 and one module is joined with another, LED 511 willilluminate to confirm to the operator that the modules are joinedcorrectly and that electrical contacts have been made. LED 511 mayoptionally include a timer or be coupled to data bus 106, 107 to limitthe length of time LED 511 flashes.

In an additional possible embodiment of the invention, LED 511 may alsobe coupled to a module microprocessor. When power is supplied to themodule, the module microprocessor can initiate a series of modulesystems self-checks that query and verify the operational status of themodule's subcomponents and optionally any attached elements. If theself-checks are concluded satisfactorily, LED 511 may blink or flash afirst sequence; and if any of the self-checks fail, LED 511 may blink orflash a second sequence. For example, if when a navigation module isjoined to a power module and all navigation systems are functioningproperly, LED 511 may simply remain lit without flashing for a period of5 seconds. If, however, a navigation component failed the self-checksequence, the module microprocessor could command LED 511 to steadilyblink, for example, at the rate of one flash every half second.

An alternative embodiment of the invention, shown in FIGS. 5D-5F, uses athreaded connection to join the modules together. In the embodiment ofFIG. 5D, a male threaded connector 550 threads into a female connector560. In the embodiment of FIG. 5D, CAN bus 106, 107 is located about thecenter of the module as illustrated in FIGS. 5E and F. The thread countof male connector 550 is such that when paired with female connector 560and screwed into place, CAN bus 106 and 107 align properly with theircounterpart in the opposing module and the proper connections are made.As in the previously described embodiment, an LED 511 may be included tovisually confirm proper connections and a sealing gasket 540 included tocreate a water tight seal, protecting the electrical connections andpreventing corrosion.

Should there exist certain modules that should not be connected to eachother, or modules that should be connected in a certain sequence, thenthe male and female ends of such modules can be specially sized orconfigured. In this manner, modules cannot be mated with an incompatiblemodule or mated in an unacceptable sequence. For example, if one modulecontains hazardous cargo, there may exist a preference to avoid placingthat module next to an ignition source such as the power module, or nextto a communications module.

Modules can also be color or visually coded to visually indicate thetype of module to the operator. For example, propulsion modules could becolored yellow; power modules colored green, and hazardous modulescolored bright orange. In this manner, an operator can readily identifythe type of module or element without having to read a placard or lookfor other identifying indicia. This feature also assists with avoidingthe pairing of incompatible modules. According to one embodiment of theinvention, the pattern or color may be included as part of the modulemanufacturing process by simply selecting the fabrication material to beof a certain color. The exterior of vehicle 100 modules may optionalinclude reflective tape or material to assist with locating andretrieving vehicle 100.

At the conclusion of a mission, the modules can be separated from eachother and returned to storage for later use and configuration of a newvehicle. To separate the attached modules, the modules are simplyrotated in an opposite direction from the direction of attachment. Inthe embodiment of FIGS. 5A-5C, this act causes pins 520 to unseat fromand clear pin slots 530. In the embodiment of FIGS. 5D-5E, maleconnector 550 is simply unscrewed from female end 560. The constructionof the male and female connectors as shown does not damage or introducewear on any of power buses 105 or data buses 106, 107.

1.2 Module Data Bus and Electrical Distribution System

Vehicle 100 may optionally include an electrical distribution system inthe form of a power bus 105; and a data bus 106, and 107 for routingelectrical power and data between modules. In a preferred embodiment ofthe invention, power and data buses 105, 106 and 107 comprise aController Area Network (CAN) bus commonly used in modern automobilesand described in the document: “CAN Bus Explained—A Simple Intro (2020)”by CSS Electronics and in “Introduction to the Controller Area Network,”by Texas Instruments; the complete contents of which are incorporatedherein by reference.

One advantage of the CAN bus architecture is that it permitsmicrocontrollers to communicate with each other and share data betweenapplications without the need for an additional host computer. The CANmessage based system ranks vehicle commands according to the CAN busdefined logic and gives priority on the CAN bus to urgent commandsfollowed by lower priority message traffic.

FIG. 5B shows an end view of the female connector portion 510 of FIG. 5Ain which a CAN bus architecture can be seen. The CAN bus includes twowires CAN-High (CAN-H) 107 and CAN-low (CAN-L) 106 for carrying datasignals. FIG. 5B also shows power bus 105. Other bus systems known tothose of skill in the art may be employed, such as for example, an ARINC429 bus or IEEE 802.11 architectures.

According to a preferred embodiment of the invention, the electricaldistribution system of vehicle 100 includes two wires (+/−) 105 thatform the power bus. The power bus nominally carries 30 volts DC at 20amps. Power can be supplied by batteries within each module or a singlebattery module that routes power via the power bus 105 to connectedmodules. A solar cell may also be included on the power module torecharge the batteries or to supply power directly.

1.3 Magnets for Modular External Elements, Transit, and Drive Systems

In prior art vehicles external devices and attachments must mate withthe main body of the vehicle via a shaft or other mechanical attachmentthat penetrates the hull. The hull penetrations of the prior art allowdirt and particulate to enter the interior of the vehicle. Thesecontaminants can in turn compromise the electrical contacts betweenconnectors and circuitry on the interior of the vehicle. Buildup ofthese contaminants in the form of grime, can also foul the operation ofmoving parts within the vehicle. When the vehicle comprises a UUV, theinterior of the vehicle must be sealed off to prevent the ingress ofseawater and prevent capsize or loss of the vehicle.

Hull penetrations, especially those for transmission of motion, musttherefore be carefully designed and maintained. Hull penetrations thusadd significant cost to vehicle design, fabrication, and maintenance.Prior art methods for sealing hull penetrations rely on a combination ofepoxy “potting”, requiring semi-permanent assemblies; elastomer seals,which can degrade with time; or novel mechanical sealing methods,requiring stringent design and fabrication considerations. When thevehicle is a UUV, even partial failure of these seals provides an avenuefor water ingress that endangers sensitive electronics or corrodesinternal components.

The magnetically coupled drive systems and control surfaces of thepresent invention eliminate the costs and failure points related toshaft seals and hull penetrations in prior art unmanned vehicles. Aconfigurable vehicle according to the present invention minimizes oreliminates the need for hull penetrations by employing magnetics toattach certain configurable components to the exterior of the vehicle.Magnets may also be employed in the drive and propulsion system of thevehicle to provide similar advantages in minimizing hull penetrationswhile additionally providing an efficient and pollution free means ofvehicle propulsion.

1.3.1 Overview of Magnets and Diametric Magnet Principles

FIGS. 6A-D show a brief explanation of ways in which a magnet may bemagnetized. According to a first method in FIG. 6A, an axiallymagnetized magnet 1100 is magnetized along a horizontal axis 1102, whereN and S poles are on either the top or bottom. When two axiallymagnetized magnets 1100 are aligned about axis 1104 with opposite polesfacing each other as shown in FIG. 6B the magnets attract and a magneticforce 1105 pulls the two magnets toward each other. When two magnets1100 are aligned about axis 1104 with similar poles facing each other, amagnetic force 1106 repels the magnets away in opposite directions, asalso illustrated in FIG. 6B.

According to a second method for polarizing magnets, illustrated in FIG.6C, diametrically magnetized magnets 1110 are magnetized to create N andS poles along the left and right sides of a vertical axis 1116. Asillustrated in 6D, the principles of magnetic attraction and repulsionpreviously illustrated in FIG. 6B, can be used by magnets 1100 and 1110to position, drive, or release apparatus by setting magnets in motionrelative to each other.

In FIG. 6D, when a first diametrically magnetized magnet 1110 spinsabout axis 1116, and a second diametrically magnetized magnet 1117 spinsin the same direction 1118 at the same rate, the opposite N-S poles tryto remain aligned. When one magnet, e.g. 1110 accelerates or stops, arepulsive force caused leg similar (N-N) poles temporarily being inalignment causes the remaining magnet 1117 to spin to re-achieve analignment of opposite N-S poles. Spinning diametrically magnetizedmagnets in this manner is leveraged by the invention to eliminate theneed for hull penetrations that would otherwise be needed in the priorart to attach or actuate moving parts such as for example, forpropulsion, payloads, ballasting systems, or control surfaces. Theforces created by attraction of opposite magnetic poles; and therepulsion of similar magnetic poles is also used by embodiments of theinvention to secure fixed or non-moveable modular elements to theexterior of the vehicle.

According to an embodiment of the invention, diametrically magnetizedneodymium magnets 1100 and 1110 comprise of neodymium iron boron (NdFeB)magnets due to the strength of their magnetic field compared to theirsize. Although magnets 1100 and 1110 are shown in FIG. 6 as cylindrical,any shape magnet may be diametrically magnetized.

1.3.2 Mounting Fixed External Configurable Elements to Modules

The alignment of opposite magnetic force and the creation of anattracting magnetic force can be used to secure a fixed configurableelement to the exterior of vehicle 100 as shown in FIG. 7 . In FIG. 7 amagnet 1700 having a first pole orientation is located on the interiorof vehicle 100 proximate to the location 1702 where a modular part 1704is to be fixedly mounted. A plurality of attachment locations 1702 maybe included along the periphery of vehicle 100 and its componentmodules. Modular part 1704 is shown as a payload or ballast in FIG. 7 ,but can be any type of modular attachment desired such as for examplecargo, sensor package, or a communications package, or a camera.

On the interior of modular part/element 1704, is a magnet 1706. Magnet1706 comprises a diametrically polarized magnet with opposite polarityto magnet 1700. When element 1704 is mated with vehicle 100, magnet 1706sits proximate to magnet 1700. As modular part 1704 is brought intoproximity to the mating surface on vehicle 100, magnets 1700 and 1706attract and the resulting magnetic force secures and holds externalconfigurable element 1704 into place. An optional pair of guide andlocking pins 1708 can be used to align element 1704 and magnets 1706 and1700. Pins 1708 also provide additional mechanical attachment of element1704 to the hull of vehicle 100.

Fixed external elements attached externally to vehicle 100 may include avariety of objects and types of devices. These external elements mayinclude, but are not limited to, landing feet of various types andsizes, externally carried payloads or ballast, fixed position antennae,cameras, sensors, or fixed control surfaces. As will be apparent tothose of ordinary skill in the art, other types of external fixedelements may also be attached to vehicle 100 using the method andapparatus described above.

1.3.3 Mounting Detachable Elements to Modules

The attachment mechanism of FIG. 7 can be further modified such thatelements may be detachably secured to vehicle 100 as shown in FIGS. 8-10. Although the discussion of FIGS. 8-10 describes ballast or cargo asthe detachable element, the principles apply to any element that can becommanded to detach or release from the vehicle. The mechanisms of FIGS.8-10 may also be used to carry and release cargo or other payloads inlieu of or in addition to ballast.

In the mechanism of FIG. 8 magnets 1700 located on the interior ofvehicle 100 are no longer secured to the hull in a fixed manner as wasshown in FIG. 7 . Magnets 1700 now reside in an actuator coupling 1800which couples to a servo/actuator 1804. In operation, a release commandsignal causes servo/actuator 1804 to turn clockwise orcounter-clockwise. As magnets 1700 rotate, the attractive force of theoriginal N/S and SN opposite pole pairing as drawn reverses and becomesa repelling force. The repelling force jettisons payload 1704 fromvehicle 100.

Also shown in FIG. 8 is an optional Hall Effect sensor 1810. Hall Effectsensor 1810 is embedded in the exterior of hull 100, secured by epoxy,and covered by μ metal shield. Hall Effect sensor 1810 detects whenpayload/ballast 1704 has been released by detecting the presence orabsence of the magnetic field between diametrically magnetized neodymiummagnets 1700 and 1706. As known to those of ordinary skill in the art, μmetal shields electronics from low-frequency or static magnetic fields.A shield 1820, formed of μ metal or other magnetically shieldingmaterial, covers Hall Effect sensor 1810 to eliminate interference fromthe magnetic field created by magnets 1700 and 1706.

In an alternative embodiment of the invention, as shown in FIG. 9 anoptional coiled spring 1900 may be integrated into the payload/ballast1704 or into hull 100 to facilitate movement away from hull 100. Whenservo/actuator 1804 of FIG. 8 rotates magnets 1700; magnets 1706 ofmodule 1704 also try to rotate to maintain the initial opposite polealignment. This motion, however, is constrained by locking pins 1708.This torque causes springs 1900 of FIG. 9 to coil. As the like polesalign, repel one another, and release the payload, coiled spring 1900uncoils and helps to propel module 1704 away from hull 100.

FIG. 10 illustrates yet another alternative embodiment that may also beused to carry and release detachable modules according to the invention.In the embodiment of FIG. 10 detachable element 1704 comprises magnets1706 as previously shown, plus a plurality of locking pins 1708. Theheads of locking pins 1708 are slightly larger than a locking trackguide 2000 cut into the hull of vehicle 100. The heads of locking pins1708 are also smaller than opening 2006 at the terminus of locking trackguide 2006.

Detachable element 1704 secures to vehicle 100 by inserting pins 1708 inthe guides 2000. The detachable element assembly is slid in track guide2000 until element magnet 1706 is of substantial opposite polarity to amagnet 2010 located on the interior of vehicle 100 and proximate element1704. The attractive force holds element 1704 in place.

As shown in FIG. 10 , magnet 2010 is coupled to a servo/actuatorcoupling 2020. Servo/actuator coupling 2020 is in turn coupled to aservo/actuator 2028. To automatically release or detach element 1704,servo/actuator 2028 receives a command from vehicle 100 and turnsthereby rotating magnet 2010. Inside payload 1704, magnets 1706 start torotate in an effort to maintain the original N/S and S/N opposite polealignment. This action causes the detachable element assembly and itslocking pins 1708, to slide along track 2000 until pins 1708 reachopening 2006. When the like poles of element magnet 1706 and magnet 2010align, the repelling force ejects element 1704 and pins 1708 clearthrough opening 2006.

In one alternate embodiment of the invention, locking track pins 1708are slightly longer than the depth of locking track 2000. Ejectionassist springs 1900 of FIG. 9 may optionally be included in the releasemechanism of FIG. 10 . Ejection assist springs 1708 compress up towardelement 1704 when element 1704 is attached to hull 100. Once lockingtrack pins 1708 reach opening 2006 of locking track 2000, ejectionassist springs 1708 uncoil rapidly, propelling element 1704 away. Therelease mechanism of FIG. 10 may also operationally include a Halleffect sensor to detect the release of detachable element 1704.

1.3.4 Payload and Ballast Modules

One specialized type pf releasable element is ballast. When vehicle 100comprises an UUV, one method for controlling the depth of the UUV is viause of releasable ballast. Buoyancy is the upward force on an objectwhen that object is placed in water. When vehicle 100 is neutrallybuoyant, the density of vehicle 100 equals the density of the water andthere is no net upward buoyancy force. Vehicle 100 is at equilibrium andremains at the depth it is placed. When vehicle 100 is negativelybuoyant, vehicle 100 sinks. When vehicle 100 is positively buoyant,vehicle 100 rises upward in the water and may surface.

Large, manned submarines utilize these same buoyancy principles. Asubmarine maintaining a specific depth has equalized the mixture ofwater and air in its ballast tanks to match the density of thesurrounding water. When the submarine wishes to surface, the submarineuses a blast of high pressure air to purge water from the ballast tanks.The air replaces any water in the ballast tanks. The ballast tank air isless dense than the ocean water and the sub rises to the surface.

Pressurized air ballast systems like those used in submarines arepossible but such systems are inherently complex, require extensivemaintenance and thus also add to the cost of owning and acquiring a UUV.Thrusters, or control surfaces such as bow planes in combination withpropulsion systems can be used to overcome forces of buoyancy to forceUUV 100 to maintain the desired depth. The UUVs 200 and 250 of FIG. 2include thrusters 220 which can be employed for this purpose. Use ofthrusters or the vehicle propulsion system consumes fuel or othersupplies of onboard energy and limits vehicle mission endurance.

According to one embodiment of the invention, UUV 100 includes a simpleballast module with releasable ballast weights. When the operator wantsthe UUV to seek and maintain a specific depth, the operator can assembleUUV 100 to include one or more ballast modules of sufficient weight.When UUV 100 is subsequently placed in the water, UUV 100 will then sinkto the depth at which the total combined weight of UUV 100 and theballast equals the density of the water. When UUV 100 wishes to rise upto a higher level or to surface, the onboard vehicle command and controlsystem can command UUV 100 to release ballast from one or more ballastmodules to attain the new desired depth or to surface. The use ofballast modules to manage the depth of UUV 100 decreases UUV 100'senergy consumption budget and increases mission endurance. When aballast module is used, UUV 100 need only use its propulsion and controlsurface systems to maneuver and such systems are not needed to maintainor attain a specific depth or to surface from depth.

In one embodiment of the invention, vehicle 100 includes a ballastmodule having a magnetically coupled ballasting system. The magneticallycoupled ballasting system allows ballasts of different weights to beattached to and released from the ballast module using a releasemechanism such as, for example, those described in FIGS. 8-10 . Inoperation, the operator of UUV 100 may select a detachable ballastmodule having a desired weight; or including a releasable sled loadedwith weights sufficient to attain the desired depth of operation. A UUV100 comprising the releasable ballast module or releasable sled ofweights taught by the present invention glides down to a pre-determineddepth where it is neutrally buoyant. UUV 100 then maneuvers and conductsits operations at depth. When UUV 100 completes operations at thatdepth, UUV 100 commands release of the ballast to attain a second depthor to surface.

Multiple ballast modules or multiple sleds having weights in releasablelots of known amounts can be included in the composition of vehicle 100.The use of multiple ballast modules or groups of weights on sleds allowsvehicle 100 to execute a mission profile inclusive of multiple depths ofoperation. Vehicle 100 simply commands the release of ballast to attainthe next operating depth in the mission profile.

1.3.5 Parasitic Ferry Transfer and Parasitic Station Keeping

The release mechanisms of FIGS. 8-10 can also be employed in reversesuch that vehicle 100 becomes the detachable item secured and thenreleased from a ferry vehicle; or attached to a fixed structure. Thismode of operation is advantageous when vehicle 100 cannot self-navigatefrom the point of assembly to the point of use. Such circumstances canarise when there are in route hazards e.g. wave heights that exceed theoperating parameters of vehicle 100. Use of a parasitic ferry transfermay also be advantageous when the distance between the point of assemblyand the point of use exceeds the capability of vehicle 100 to bothtransit that distance and execute the mission.

Use of a parasitic ferry transfer can also be employed to retrieve andreturn vehicle 100 from its point of use. After completion of a mission,vehicle 100 can navigate to a ferry vehicle and attach itself. The ferryvehicle inclusive of vehicle 100 can then return the vehicle to itsintended destination. These types of operations also permit vehicle 100to stay on station longer and execute mission profiles of longerduration than would be possible if vehicle 100 used its own energystores to transit. Use of a parasitic ferry also can be used foremergency recovery of vehicle 100.

For parasitic ferry operation, vehicle 100 can include a moduleincluding the release mechanism of the embodiments shown and describedin connection with FIGS. 8 and 9 ; and may also include Hall Effectsensors to detect and communicate the presence or absence of theparasitic ferry vehicle. FIG. 11A illustrates possible embodiment anduse of a detachable/release mechanism for ferry operation. FIG. 11Ashows vehicle 100 including module 2044 parasitically attached to aferry vehicle 2045. In the embodiment of FIG. 11A, ferry 2045 includes adiametrically magnetized magnet 2048 and locking pins 1708, which alsomay include optional springs 1900. Vehicle 100 can be attached andsecured by the operator by attaching vehicle 100 to ferry 2045 at thelocation of magnet 1700. When vehicle 100 reaches the point of release,vehicle 100 commands actuator 1804 to rotate, and the resulting motionof magnets 1700 creates a repelling force that separates vehicle 100from ferry 2045. Ferry 2045 can optionally include a vertical guide postthat prevents the attached vehicle 100 from rotating during release.

To autonomously reattach or attach vehicle 100 to ferry 2045, vehicle100 navigates alongside ferry 2045. Guide pins 1708 engage with the hullof vehicle 100 at the corresponding location along the hull exterior.When entering the docking mode, servo 1804 has already commanded magnets1700 to an orientation with poles opposite the fixed location of thepoles of magnets 2048. This attractive magnetic force assists withguiding vehicle 100 to proper location on ferry 2045 and alignment withthe locking pins.

The opposite construction is also possible as shown in FIG. 11 B. InFIG. 11B, vehicle 100 contains a module 2049 having fixed magnets 2052.Rotating magnets 2054 and a servo 2056 are located aboard ferry 2045.Any of the unoccupied magnetized locations and attach points on vehicle100 will serve as a suitable mating spot for pairing with magnets 2054.When vehicle 100 is to be released, ferry 2054 rather than vehicle 100initiates the command for separation. Once released, vehicle 100executes its mission.

FIGS. 11C-E shows a cross section of yet another ferry or structuredattachment mechanism that can include a manual release key 2059 locatedinside ferry 2045. In the embodiment of FIG. 11C, key 2059 couples to apivotable adapter 2060 having guide tracks 2062. Mating pins 2064 havingsprings 1900, can be located on vehicle 100 and fit into guide tracks2062. In FIGS. 11C-E, adaptor 2060 is shown located on ferry vehicle2045. Reattaching or attaching vehicle 100 to ferry 2045 works asdescribed in the previous paragraph.

Use of the adaptor prevents the entire ferry vehicle 2054 or vehicle 100from rotating in the guide tracks 2062. As drawn in FIG. 11D, whenvehicle 100 is to be released, the operator turns key 2059 to rotatemagnets 2063 which causes adaptor 2060 to rotate and pins 2064 to moveinside the vehicle guide tracks 2062 until reaching stop 2063. Therotational stop prevents vehicle 100 from rotating while adapter 2060rotates in slots 2062. Magnets 2063 and 2054 are then in a N/N and S/Salignment and pins 2064 align with ejection cavity 2065. Vehicle 100 isthen pushed away from ferry 2060 by repelling force of the repositionedmagnets. Reattaching or attaching vehicle 100 to the ferry via therelease mechanism just described simply works in reverse. Manuallyturned key 2059, can also be replaced by a servo mechanism to turnadapter 2060 as illustrated in previous embodiments.

A third option for using magnets for parasitic ferry transport is themechanism shown in FIG. 11F. In this embodiment, one or more energizedmagnets 2066 is included in the nonferrous body of ferry 2045. Whenmagnet 2066 is energized, any of the fixed magnet structures 1700 ofFIG. 7 included in vehicle 100 and not otherwise occupied; oroptionally, any of the unoccupied magnet structures 2010 or 1700 ofFIGS. 10 and 8 ; will be attracted to energized magnets 2066. Oncevehicle 100 navigates near enough to ferry 2045 it may be “captured” bythe energized magnet 2066 without worrying about alignment of pins 1708.Optionally, an operator may place vehicle 100 proximate to energizedmagnets 2066 to secure vehicle 100 to ferry 2045 for transport. Torelease vehicle 100, ferry 2045 or the operator simply commands magnets2066 be de-energized. Upon that event, the magnetic attraction ceasesand vehicle 100 drifts away from ferry 2045, free to execute itsmission.

Any of the parasitic ferrying methods described in connection with FIGS.11A-11F may also be used to affix vehicle 100 to a stationary object.The sole difference being that instead of a moveable ferry 2045; a fixedobject such as a buoy, oil rig, wharf, or other structure is substitutedtherefor. Navigating to and then attaching itself to a fixed structureallows vehicle 100 to be easily retrieved from a known location.Navigating to and then attaching itself to a fixed structure also allowsvehicle 100 to proceed to a test or observation location, remain therewithout expending energy to station-keep, detach itself and return. Whenvehicle 100 is used for collection of scientific data from remotelocations, attaching at a fixed and determinate location often aids inthe precision measurement of results.

1.3.6 Mounting Moveable External Configurable Elements To Modules

Various control surfaces on vehicle 100 can be used to adjust the pitch,roll, or yaw of the vehicle. As previously illustrated in FIGS. 1-2 ,when vehicle 100 comprises an UUV, the control surfaces may include asail plane or a dorsal fin 120, flippers 122, rudders and stabilizers124. Moveable external configurable elements such as control surfaceshelp to steer vehicle 100 and to control motion about the pitch, roll,and yaw axis. Any number or different types of control surfaces ormoveable external elements may be mounted to vehicle 100 modules. Othertypes of moveable external configurable elements may include, forexample, a camera, or antennae. The modularity of the present inventionpermits different types, sizes, shapes and characteristics of moveableexternal control surfaces and elements to be attached as desired toconfigure vehicle 100 as wished.

In the prior art, these moveable control surfaces are controlled throughdrivetrains and shafts penetrating through the hull of vehicle 100,requiring the use of epoxies and other sealants to prevent water fromentering the interior of the hull at the point of penetration. Epoxiesand other sealants degrade over time, causing avenues for water andother contaminants to enter the interior of vehicle 100 and damagesensitive electronics. Magnetically coupled control surfaces eliminatethese avenues by removing the need to penetrate the hull.

FIG. 12 illustrates a magnetically coupled control surface ormoveable/positionable element 2099. Inside of vehicle 100, an internaldiametrically magnetized neodymium magnet 2100, adhered with epoxy to acoupler 2102, couples to servo/actuator 2104 the motion of which movesmagnet 2100 to control the positon of element 2099. A seconddiametrically magnetized neodymium magnet 2108 is adhered with epoxy toa control surface coupling 2120. A coupling retainer 2125 holds controlsurface coupling 2120 against hull 100. Control surface couplingretainer 2125 reduces the chances of losing control surface 2120 toover-oscillation or impact. According to one possible embodiment of theinvention, coupling retainer 2125 secures to hull 100 by several controlsurface coupling retainer fastening bolts 2130 which do not penetratethe hull.

A drive train shaft 2135 changes the position of control surface ormoveable element 2099. Control surface drivetrain shaft 2135 couples toexternal diametrically magnetized neodymium magnet 2108 through controlsurface coupling 2120. A nut 2140 located at the end of control surfacedrivetrain shaft 2135 secures control surface/moveable element 2099 todrive shaft 2135.

In the embodiment as drawn in FIG. 12 parts 2099 and 2120 are shown asseparate parts. Parts 2099 and 2120 may, however, be fabricated as asingle piece. When parts 2099 and 2120 are fabricated as a single piece,drive shaft 2135 and nut 2140 are no longer necessary. As magnet 2108rotates, the combined assembly of parts 2120 and controlsurface/moveable element 2099 also rotates. Such a construction reducesthe total number of parts comprising the moveable element or controlsurface and may reduce overall cost and complexity.

In operation, a signal is sent from vehicle 100 command and controlsystem to servo/actuator 2104. Servo/actuator 2104 is capable of turningcoupling 2102 in either a clockwise or counter-clockwise direction. Asinternal diametrically magnetized neodymium magnet 2100 rotates,external diametrically magnetized neodymium magnet 2108 starts torotate, as both magnets try to keep a N/S and SN pairing. The motion ofmagnet 2108 moves control surface 2099 via the motion of drive shaft2135.

Although the previous paragraphs explain the construction and operationof moveable external attachments in the context of moveable controlsurfaces, the principles described above apply equally to theconstruction and operation of additional types of moveable/positionableexternal elements. For example, moveable external elements mayadditionally include thrusters, antennae and sensors that rotate and aremoveably affixed to the exterior hull portion of vehicle 100.

1.3.7 Propulsion Module and Propulsion Systems

Attachment and drive systems similar to these shown in FIG. 12 may alsobe included in vehicle 100 to comprise propulsion systems and modules.As previously described in connection with both fixed and moveableexternal attachments, prior art propulsion assemblies require hullpenetration for mechanically connecting the propeller assembly to theinternal motors and drive systems. The configurable propulsion systemsof the present invention avoid the need for such potentially problematichull penetrations.

Prior art propulsion systems also typically include a shear pin. Theshear pin breaks, or shears, whenever the propeller load exceeds acertain limit as might happen when the propeller stops turning becauseit has been fouled by seaweed or debris. If the motor kept commandingthe propeller to rotate when it could not, the resulting torque would betransferred to the motor, and perhaps to the entire vehicle, causingsignificant and perhaps irreparable damage up to an including potentialloss of the vehicle. The shear pin is designed to break and detach thepropeller under these conditions to prevent such damage. When the shearpin breaks, however, the propeller is lost and the vehicle renderedwithout propulsion and unable to complete its mission. The configurablepropulsion system of the present invention does not require a shear pinand recognizes and avoids the problems of the prior art.

FIG. 13A shows a side view of a propulsion module 2199, FIG. 13B showsan end view, and FIG. 13C shows a cross sectional view. Propulsionmodule 2199 may include threads 2201 for attaching module 2199 to theremainder of vehicle 100. Although a threaded system such as that shownin FIGS. 5D-5F is shown in FIG. 13A, any mating system may be usedincluding the systems of FIGS. 5A-5C.

As seen in the end view of FIG. 13B and the cross sectional view of FIG.13C, propulsion module 2199 includes components internal to hull 100:magnet 2202, servo coupler 2203, motor mount 2207, DC motor 2208, andmotor controller 2209. FIG. 13D shows a cross sectional view of analternative embodiment of propulsion module 2199 having these componentsarranged in an alternative construction. As shown in FIGS. 13B-13D,propulsion module 2199 additionally includes a propeller assembly 2210that couples magnetically to the remaining portion of propulsion module2199. The propeller assembly 2210 includes: a magnet 2214 which rests incoupler 2218 and which is coupled via a drive shaft 2220, which can belocated internal to a propeller housing 2225, to a propeller 2228. A nut2229 secures propeller 2228 to drive shaft 2220. A mechanical coupling2230 includes fasteners 2235 (FIG. 13D) to secure assembly 2210 to theremainder of the propulsion module 2199. Mechanical coupling 2230stabilizes the turning motion of propeller assembly 2210 and prevents itfrom vibrating off hull 100. Propulsion module 2199 may also includeHall Effect sensors (not shown in FIG. 13 ) as shown and describedpreviously to detect the presence or absence of propeller assembly 2210or of propeller 2228.

In operation, motor 2209 receives instructions from vehicle 100'scommand systems to introduce, increase, or decrease power to DC motor2208. Rotating shaft 2240 causes internal diametrically magnetizedneodymium magnet 2202 to rotate. Motor mount 2207 isolates DC Motor 2208from the vibrations caused by spinning shaft 2240 and the magnetassembly.

Motor 2208 can generate a significant amount of heat during operation.As previously discussed, the interior volume of propulsion module 2199can include engineered fluid for thermal management. As seen in thecross section of FIG. 13D, the walls of module 2199 can additionallyinclude capillaries 2241 fluidly coupled to the interior volume ofmodule 2199. Capillaries 2241 help transfer heat to the exterior ofvehicle 100. The wall structure including capillaries 2241 can bedesigned for the needed structural strength according to techniquesknown to those of skill in the art. Incorporating capillaries 2241 intothe wall of propulsion module 2199 or any other vehicle 100 module isachievable using any manufacturing technique, but is especially easy tobuild when employing additive manufacturing.

As DC motor 2208 rotates internal diametrically magnetized neodymiummagnet 2202, magnet 2214 also rotates as both diametrically magnetizedneodymium magnets strive to keep a N/S and SN pole attraction. As magnet2214 rotates, drive shaft 2220 turns causing propeller 2228 to spin. ATeflon or other wear surface 2245 (FIG. 13C) may optionally be includedto minimize friction and wear between propeller assembly 2210 and theremainder of propulsion assembly 2199.

An airgap 2252 exists between the rotating magnets and the hull or partexterior. In the absence of airgap 2252, internal diametricallymagnetized neodymium magnet 2202 and external diametrically magnetizedneodymium magnets 2214, would bear against the exterior wall and rotateagainst it, wearing and eventually compromising the wall material.Inclusion of airgap 2252 reduces the wear on propulsion module 2199.

The fixed pitch propeller 2228 rotates to propel vehicle 100 to moveforward. Changing the direction of rotation for propeller 2228 willpropel vehicle 100 backward. A Hall Effect sensor (not shown in FIG. 13) located just below internal diametrically magnetized neodymium magnet2202, measures the strength of the magnetic fields created by magnets2202 and 2214. The measurements detected by the Hall Effect sensor areindicative of the proximity, position, and/or speed of the magnets andare especially useful for indicating propeller RPM. This data iscommunicated via data busses 106 and 107 the vehicle's command system tocontrol operation of propulsion module 2199.

External retention collar 2230 helps to constrain motion of propellerassembly 2210 to the rotational direction and to minimize vibration andout of plane motions. Retention collar 2230 attaches to propulsionmodule 2199 by propeller caps 2260 and fasteners 2235. When vehicle 100is in use, external retention collar 2230 makes vehicle 100 moreresilient to impact, reducing the chances for propeller 2228 orpropeller assembly 2210 to be dislodged.

As discussed in connection with FIG. 12 , the overall complexity andpart count for propulsion assembly 2210 can be reduced by eliminatingnut 2229 and drive shaft 2220. Propeller housing 2225 and mechanicalcoupler 2218 can be fabricated as a single piece. In this configuration,when magnets 2214 rotate, the entire combined assembly rotates, therebyturning propeller 2228.

One advantage of the propulsion module of the present invention, is thatwhen the propeller is fouled and cannot rotate, the propeller need notbe severed from the vehicle or lost. If propeller 2228 stops rotating,drive magnet 2202 simply continues to rotate. The driven magnet, 2214will “cog” or “slip” as it tries to maintain the N/S alignment, but thismotion will not impose harmful torques on propeller assembly 2210, motor2208, or the remainder of vehicle 100. Retainer pins 2235 will keeppropeller assembly 2210 from detaching from the vehicle. Once the debrisor object clears the propeller and it is no longer fouled, propellerassembly 2210 and propulsion module 2199 return to normal operation. Themission can be completed without the need to retrieve a stranded vehicleand replace the propeller. This advantage of the present invention alsoapplies to moveable configurable elements such as moveable controlsurfaces that can also become fouled or impeded through their range ofmotion.

FIGS. 14A and 14B show an alternative embodiment of a propeller assembly2300 having counter rotating propellers 2310 and 2311. Propellers 2310and 2311 include a plurality of individual blades 2312 a and 2312 bsecured to a housing. Blades 2312 a and 2312 b are preferably ofsubstantially opposite pitch. As draw in FIG. 14A, the blades 2312 ofpropeller 2310 secure to housing 2313 and the blades of propeller 2311secure to housing 2314. Housing 2313 is coupled to housing 2314 by bolts2317 and plate 2318. Housings 2313 and 2314 as well as blades 2312 maybe made using additive manufacturing techniques such as 3D printing.

As seen in the cross section of FIG. 14B, propeller assembly 2300 alsoincludes a larger diameter inboard drive shaft 2319 and a smallerdiameter shaft 2320. A nut 2323 at the end of drive shaft 2320 securesand retains housings 2313 and 2314. Smaller diameter shaft 2320 extendsto fit inside larger diameter shaft 2319 and both shafts 2319 and 2320couple to a bevel gear box 2325. Gear box 2325 contains the gearingmechanisms that drive shafts 2319 and 2320 as is known to those of skillin the art, which in turn are coupled to rotating magnets 2214 (notshown in FIG. 14 ) that turn the gears in gear box 2325.

The entire propeller assembly couples to the remainder of the propulsionmodule 2199 as shown and described previously in FIG. 13 . As DC motor2208 causes magnets 2202 to rotate, magnets 2214 of propeller assembly2300 also rotate. The rotation of magnets 2214, in turn cause the gearsin gearbox 2325 to rotate shafts 2319 and 2320 and spin propellers 2311and 2310.

Propellers 2311 and 2310 counter-rotate, with one propeller andpropeller shaft spinning clockwise and the second spinningcounterclockwise. In single propeller designs, the single propellerintroduces a yawing moment, or turning tendency, for which the vehiclecontrol systems must compensate to keep the vehicle oriented as desired.With the propeller assembly 2300 of the present invention, the counterrotating propellers each cancel out the yawing moment of the remainingpropeller, thereby improving vehicle handling and reducing the need foradditional control forces to keep the vehicle oriented.

1.4 Vehicle Scuttle Module

When vehicle 100 comprises a UUV, the vehicle operator may wish to allowfor scuttling of the vehicle. Scuttling the vehicle may be desirable toprevent unauthorized access to vehicle 100, to prevent vehicle 100 frombeing detected by an adversary, or to halt vehicle 100 operations whenextreme hazards exist. Other reasons for scuttling vehicle 100 mayexist.

According to an embodiment of the invention, vehicle 100 includes ascuttle module to autonomously scuttle the vehicle in predeterminedconditions; or upon receiving an external communication to do so. FIGS.15A-15B illustrate embodiments of a scuttle module 2360 according to theinvention. In the embodiment of FIG. 15A, scuttle module 2360 includes aset of operable doors 2362 and 2364. When closed, doors 2362 and 2364prevent water from entering module 2360. If vehicle 100 is to bescuttled, a command is sent via CAN bus 106, 107 to a modulemicrocontroller 2366 which then commences operation of DC motors orservos 2368 and 2369. Motors 2368 and 2369 cause shafts 2372 and 2374 toturn and via linkages 2376 and 2378, doors 2362 and 2364 pivot on theirrespective hinges 2380 and 2382 exposing openings 2384 and 2386 to thesea. Optionally, doors 2362 and 2364 can be constructed to slide in atrack by coupling the door to a gear operated by DC motors 2368 and2369. Other linkages and mechanisms are possible.

With doors 2362 and 2364 open to the sea, water floods the interior ofmodule 2360. The interior volume of module 2360 is sized such thatvehicle 100 propulsion and control systems will not be able to overcomethe added weight of the water, and vehicle 100 will sink. Multiplescuttle modules 2360 can be used to configure vehicle 100 to ensure thata volume of water sufficient to scuttle the vehicle floods the modules.

In lieu of hinged doors, any of vehicle 100's modules can alsooptionally include voids covered initially by water tight doors. Thesedoors can be opened using the rotational magnet mechanisms illustratedin any of FIGS. 8-10 . When commanded, the servo rotates the attachedmagnet, causing the magnet coupled to the watertight door to rotate andopen the door. With the watertight doors of the modules commanded open,water floods the vehicle causing it to sink.

FIG. 15B illustrates yet another alternative embodiment of a scuttlemodule 2390. In the embodiment of FIG. 15B, module 2390 includes a smallexplosive charge 2392. Explosive charge 2392 is coupled to a detonator2394 according to principles known in the art. If vehicle 100 is to bescuttled, a command is sent via CAN bus 106, 107 to trigger thedetonator. For additional safety, the command may be routed through alocal processor 2396 included with module 2390 that performs a series ofcheck sums, key exchange, or other secure validation of the command orcommand sequence. If the command sequence is valid, processor 2396forwards the detonation command to detonator 2394. The resultingdetonation of explosive charge 2390 is sized large enough to break apartvehicle 100 and send her to the bottom. According to additionalembodiments of the invention, module 2390 also includes electrical faultisolation systems to prevent errant currents or short circuits fromtriggering detonator 2394.

Constructing a scuttle module according to the embodiment of FIG. 15B,requires operators receive specialized training in the safe handling,use, and storage of module 2390. Painting or coloring module 2390 hazardorange and labeling the module with appropriate safety placards is alsorecommended. These actions provide a visual clue to the operator thatmodule 2390 requires special handling and care when being attached tovehicle 100 during vehicle 100 use.

2.0 Vehicle Systems

Vehicle 100 includes both a physical systems and a logical systemsarchitecture. Vehicle 100 physical architecture includes hardware suchas computing architecture, power systems, power distribution buses,internal storage and memory, device controllers, sensors, and databuses. Vehicle 100 logical systems include command and control logic andstability and control logic.

2.1 Hardware Systems Architecture

FIG. 16 contains a hardware systems diagram of vehicle 100. In thediagram of FIG. 16 , a set of onboard hardware components 2400 includeseveral hardware subsystems. According to one embodiment of theinvention, a central computer 2410 interfaces with the remaining vehiclesubsystems and reads and writes commands and data to other vehicle 100components via a USB or CAN Bus 2415. In a possible embodiment of theinvention, computer 2410 comprises a commercially available Raspberry Picomputer mother board manufactured by DigiKey, the technical overview ofwhich is incorporated herein by reference. In one possible embodiment ofthe invention, vehicle 100 may include a discrete command module thatincludes computer motherboard 2410 and associated memory andelectronics.

Motherboard 2410 is powered by a vehicle 100 power module 2420. Powermodule 2420 may be physically collocated with motherboard 2410 orcomprise a separate configurable power supply module with differenttypes or quantities of power. In one embodiment of the invention, powermodule 2420 includes a battery 2425 as a power supply. In the hardwaresystems diagram of FIG. 16 , power module 2420 supplies 5V DC tomotherboard 2410 via a power conditioning device, regulator 2428. Apower distribution system, or switches, 2430 route power to othervehicle 100 components needing electrical power. As described above,power is distributed throughout vehicle 100 via power bus 105.

Power and data signals are shared with peripherals using a standardinterface and interface definition such as, for example, Pixhawk dronehardware interface and interface standards 2435, available fromwww.pixhawk.org the definitions of which are incorporated herein byreference. Peripherals can include lights 2440 that may be used as ameans of communication or as a source of illumination for a camera 2445.The position of camera 2445 can be fixed or can be controlled by acamera tilt servo 2450. When vehicle 100 comprises a UUV or otherwatercraft, peripherals may additionally include one or more leakdetectors 2455. Leak detectors 2455 may be distributed throughoutvehicle 100 to detect the ingress of water into individual modules thatmay cause vehicle 100 to sink or capsize. Additional sensors or payloads2460 as previously described may also be included within the hardwaresystems of vehicle 100. An electronic systems controller(s) 2465interfaces with power distribution system 2430 to control peripheralsaccording to instructions received from computer 2410.

Onboard vehicle systems 2400 may interface with shore-side controllerhardware 2470. According to one embodiment of the invention, controllerhardware 2470 comprises an electronic tether 2475 coupled to a Fathom Xendpoint 2480. Tether 2475 and Fathom X device 2480, couple to vehicle100 via an Ethernet link 2485 allowing the vehicle operator to configurevehicle 100 systems via motherboard 2410. Tether 2475 can optionallyalso couple to other vehicle sensors 2460 via an Ethernet link 2488 oranother communications bus such as, for example, an RS 485 bus 2490. Anetwork switch 2495 controls connections to any given peripheral or to aspecific communications bus by shore-side controller hardware 2470.

2.2 Software and Logic Systems Architecture

FIG. 17 contains a block diagram of a vehicle 100 software systemaccording to one embodiment of the invention. In the systemsarchitecture of FIG. 17 , the Raspberry Pi computer 2410 includes avariety of firmware or software logic for controlling and operatingvehicle 100. A first logical component 2500 which may comprise MAVProxysoftware produced by ArduPilot.org reads and writes data andinstructions via a USB or other electronic data port/modem 2415.Optionally, Mathworks of Natick, Mass., makers of MATLAB and Simulinkmathematical computing software, has under development command andcontrol logic that may also be included to form logic component 2500 andto configure vehicle 100, once such tools are completely developed. Theinstructions for controlling and operating vehicle 100 may includecommand and control logic instructions 2505 exchanged according to thePixhawk interface 2435. Logic 2500 also receives data and telemetry 2510received from peripherals or attached devices via interface 2435 and USBport 2415. As discussed in greater detail below, logic module 2500 mayalso include logic for navigating and positioning vehicle 100 viamanipulation of propulsion module 2199 and vehicle 100 control surfacesaccording to navigation data and other mission parameter data andfunctions stored and executed by logic 2500 and onboard computer 2410.

A second vehicle logic module 2520 operates onboard cameras and optics.In one embodiment of the invention, software module 2520 comprisesraspivid software which reads and writes data and instructions from acamera 2445. According to one embodiment of the invention, camera 2445comprises a Raspberry pi camera procured through DigiKey, the completetechnical specification of which is incorporated herein by reference.

According to one possible embodiment of the invention, visual datacaptured by camera 2445 is written to software module 2520 and raw imagedata then transmitted (or rewritten) by software module 2520 to astreaming software logic function 2525. Streaming function 2525 can thenupload or stream data 2528 off of vehicle 100 to shore-side computers2530 or other data and telemetry receiving devices.

As will be readily apparent to those of ordinary skill in the art, thevehicle software architecture 2410 of FIG. 17 may be implemented insoftware, firmware, or ASIC devices and is not limited to the specificsoftware shown in FIG. 17 . The logic functions may also be apportionedacross various software routines or firmware and need not be strictlysegregated into the software modules as drawn.

According to one possible embodiment of the invention, vehicle 100interfaces with a shore-side computer 2530 via a controller 2470 (shownin FIG. 16 ). Topside computer 2530 may include a vehicle configurationand control software, QGroundControl 2540 found at qgroundcontrol.comand managed by the Dronecode Project, the complete technical descriptionof which is incorporated herein by reference. Software 2540 mayoptionally interface with a joystick 2545 which may serve as a means foroperator control of a tethered vehicle 100 when not operatingautonomously; or as means for inputting data to QGroundControl software2540. Joystick 2545 provides data to software 2540 via a USB port 2550or other electronic port known to those of skill in the art.

Command and configuration data and information exchanges 2555 and 2556received from vehicle 100, may be communicated to/from topside computer2530 via a USB or Ethernet link with Raspberry Pi computer 2410 viasoftware module 2500 and software module 2540. As noted in connectionwith the description of the vehicle 100 logic architecture, topsidelogic 2530 may be implemented using other software, firmware or ASICmodules as is known in the state of the art and is not limited to thespecific software configuration shown in FIG. 17 .

Topside software and computer 2530 may be used by operators of vehicle100 to configure vehicle 100 systems, load mission parameters andinstructions, and to validate the status of vehicle 100 systems,modules, sensors, payloads and other elements and components. FIG. 18shows an example of a vehicle user interface 2600. In the example userinterface of FIG. 18 , a left side menu 2610 allows the user to selectvarious top level systems for further parameter definition andconfiguration. As illustrated in FIG. 18 , a summary page is selectedand area 2620 of the user interface summarizes the current status andconfiguration of various onboard systems including: navigation sensorpackages 2625, power systems 2630, safety systems 2635, frame parameters2640, lights 2645, and camera systems 2650. In one possible embodimentof the invention, user interface 2600 comprises ARDUSub software orfirmware found at www.ardusub.com manufactured by BlueRobotics, thespecifications of which are incorporated herein by reference.

Other user interface systems may be used with the present invention, andthe invention is not limited to the specific software or user interfaceshown. In addition, as described previously, vehicle 100 may beconfigured for a variety of missions and uses, and may include a varietyof different types of sensors, telemetry, power, safety, and otheronboard systems not depicted in FIG. 18 as drawn. The option toconfigure, status and set parameters for such additional systems is alsopreferably available to the vehicle operator via user interface 2600 asdesired.

2.3 Vehicle Stability and Control

In prior art vehicles of fixed design and configuration, the vehiclemass and control configurations are established in advance and areknown. Thus, when operating prior art vehicles in an autonomous mode,the vehicle's moments of inertia and its stability control coefficients:information needed to control and manoeuvre the vehicle remains a knownset of constants. In contrast, adding and removing modules, and addingand removing various propulsion systems, and external modular elementsto vehicle 100 alters the center of mass, center of buoyancy and thestability and control parameters of vehicle 100 each time a new vehicle100 is configured.

2.3.1 Dynamically Determined Stability and Control Logic

According to one embodiment of the invention, vehicle 100 includesonboard logic or programming that receives configuration data from eachmodule and component which makes up vehicle 100. Such configuration datamay include the individual dimensions and mass properties of eachattached module or component, as well as its stability and controlparameters, and/or its performance parameters and operational limits,payloads, design limits, or other information.

Data about the module or element may be collected by the operatortopside, for example by reading from a label or inscription on theelement or module, at the time of vehicle configuration. Thisinformation can then be entered and loaded into vehicle computer 2410via topside computer 2530. Vehicle 2410 via topside computer 2530.Vehicle 2410 can them compute the stability and control coefficients andcontrol laws for vehicle 100. Optionally, each individual module mayhave its information stored in a memory and a processor located aboardeach module. According to one embodiment of the invention, modules mayinclude a Beagle Bones microprocessor, coupled to CAN bus 106, 107 forthis purpose. Individual elements may also include a small read onlymemory (ROM) device, also coupled to a CAN data bus, that storesinformation about the individual element. This memory can be queried bythe microprocessor aboard the attached module, or directly from thevehicle central processing system 2410.

For example, propulsion system 2199 may transmit via CAN bus 107 and108, the type of propeller attached including data such as propellerpitch and number of blades, as well as operating limits such as maximumrevolutions and operating envelopes. Additionally, control surfaces andwing data may include lift and drag data, wing configuration, andstability coefficients. If such surfaces are not fixed, control surfacedata may include the range of motion or degrees of travel over which thesurface can be positioned. Module data may include information aboutmodule capabilities; ballast and payload contents, if any; and modulemass, moment of inertia, stability coefficients and dimensionalproperties. As will be evident to those of skill in the art, a varietyof information about each configurable attachment and individual modulemay be transmitted via data bus 107, 106 as desired to aid in operatingvehicle 100 and performing vehicle 100 mission evolutions.

According to one embodiment of the invention, when a module or componentis attached to vehicle 100, that module or component transmits via CANbus 107, 106 the configuration and characteristics data stored in localmemory within that module or component. Optionally, when a module orcomponent is attached to vehicle 100, that module or component cantransmit a module or component identification value via CAN bus 106,107. Computer 2410 has stored therein a look up table, memory, logic, orother programming that associates a set of configuration andcharacteristics data with the component identification value received.

Even with the individual module mass properties and stabilitycoefficients provided to computer 2410, the overall vehicle stabilitycoefficients, mass properties and dynamics must be calculated so vehicle100 can be controlled and operated. Various approaches may be used todynamically determine the necessary control laws and parameters. Theseapproaches include direct calculation using the known properties of theindividual modules; or empirically determining the control law values byhaving the assembled vehicle 100 execute a defined series of manoeuvresprior to departing on the mission; or some combination of both. In thelatter case, a set of stability and control coefficients can becalculated and then vehicle 100 could conduct a short test run tovalidate or refine the calculated values. Vehicle 100 also dynamicallyupdates its control parameters as it drops ballast or consumesconsumables during operation. These calculations could also beperiodically verified by vehicle 100 autonomously executing a shortseries of manoeuvres periodically during the mission to validate andupdate prior stability calculations or to just empirically determine thechanged control parameters.

Methods for dynamically calculating vehicle 100 stability and controlcoefficients include: adaptive methods, least squares regression models,Kalman filter models and machine learning models. Any of the abovemethods can be used to dynamically calculate the vehicle 100 stabilityand control coefficient and control laws. Adaptive methods include thefollowing.

a) 3 degree of freedom models: for example as described in Paine,“Adaptive Parameter Identification of Under-actuated Unmanned UnderwaterVehicles; a Preliminary Simulation Study,” in Oceans 2018 MTS/IEEECharleston, IEEE, October 2018, pp 1-6; and incorporated herein byreference.

b) decoupled 6 degree of freedom models: for example as described in,Smallwood, “Adaptive Identification of Dynamically Positioned UnderwaterRobotic Vehicles,” IEEE Transactions on Control Systems Technology, vol.11, no. 4 pp 505-515, July 2013; and Tyler Paine et. al, “PreliminaryFeasibility Study of Adapted Parameter Identification for Decoupled,Underactuated, Unmanned Underwater Vehicles in 6 Degrees of Freedom,” apaper presented at the Yale Workshop on Adaptive Systems and Learning;each of which is incorporated herein by reference.

c) fully coupled, fully actuated 6 degree of freedom plant models: forexample as described in McFarland, “Comparative Experimental Evaluationof a New Adaptive Identifier for Underwater Vehicles,” in 2013 IEEEInternational Conference on Robotics and Automation, May 2013, pp4614-4620; Paine and Whitcomb, “Adaptive Parameter Identification ofUnderactuated Unmanned Underwater Vehicles; a Preliminary SimulationStudy,” 2018; and Harris, Paine, and Whitcomb, “Preliminary Evaluationof Null Space Dynamic Process Model Identification with Application toCooperative Navigation of Underwater Vehicles,” each of which isincorporated herein by reference. Embodiments of the invention asdescribed more below include fully coupled, fully actuated 6 degree offreedom plant models.

Additional models which may be used to dynamically calculate vehicle 100stability and control coefficients and control laws include leastsquares linear regression methods. These methods include the followingmore specific methods.

a) 3 degree of freedom models: for example as described in Hegrenaes etal. “Comparison of Mathematical Models for the Hugin 4500 AUV Based onExperimental Data,” 2007 Symposium for Underwater Technology andWorkshop for Scientific Use of Submarine Cables and RelatedTechnologies, April 2007, pp 558-567; Ridao, “On the Identification ofNonlinear Models of Unmanned Underwater Vehicles,” Control EngineeringPractice, vol. 12, no.12, pp 1483-1499, 2004 in Guidance and Control ofUnderwater Vehicles; and Graver, “Underwater Glider Model ParameterIdentification,” in Proceedings of the 13^(th) International Symposiumon Unmanned Untethered Submersible Technology (UUST), vol. 1, 2003, pp.12-13; each of which is incorporated by reference herein.

b) 6 degree of freedom models: for example as described in Martin,“Experimental Identification of 6 Degree of Freedom Coupled DynamicPlant Models for Underwater Robot Vehicles,” IEEE Journal of OceanicEngineering, vol. 39, no. 4, pp 662-671, October 2014; Martin,“Experimental Identification of 3 Degree of Freedom Coupled DynamicPlant Models for Underwater Vehicles,” Springer InternationalPublishing, 2017, pp 319-341; and Natarajan, “Offline ExperimentalParameter Identification Using Onboard Sensors for an AutonomousUnderwater Vehicle,” in Proceedings of MTS Oceans, October 2012, pp 1-8;each of which is incorporated herein by reference.

c) reduced parameter 6 degree of freedom models for example as describedin Randeni, “Parameter Identification of a Nonlinear Model: Replicatingthe Motion Response of an Autonomous Underwater Vehicle for DynamicEnvironments,” Nonlinear Dynamics, vol. 91, no. 2, pp 1229-1247, January2018; Randeni, “Implementation of a Hydrodynamic Model Based NavigationSystem for a Low Cost AUV Fleet,” in IEEE OES Autonomous UnderwaterVehicle Symposium (AUV) no. November 2018; and Harris, “PreliminaryEvaluation of Null Space Dynamic Process Model Identification withApplication to Cooperative Navigation of Underwater Vehicles,” 2018IEEE/RSJ International Conference on Intelligent Robots and Systems(IROS) IEEE, October 2018, pp 3453-3459; each of which is incorporatedherein by reference.

Kalman filter approaches for dynamically determining the stability andcontrol coefficients and control laws of vehicle 100 also exist. Kalmanfilter variants include the following examples: Tiano, “Observer KalmanFilter Identification of an Autonomous Underwater Vehicle,” ControlEngineering Practice, vol. 15, pp 727-739, June 2007; and Sabet,“Identification of an Autonomous Underwater Vehicle Hydrodynamic ModelUsing the Extended, Curvature, and Transformed and Unscented KalmanFilter,” IEEE Journal of Oceanic Engineering, vol. 43 no. 2, pp 457-467,April 2018; each of which is incorporated herein by reference.

Machine learning and neural network methods have also been developed asa method for calculating the stability and control coefficients andcontrol laws. These methods include the following.

a) machine learning methods: for example as described in Wehbe,“Experimental Evaluation of Various Machine Learning Regression Methodsfor Model Identification of Autonomous Underwater Vehicles,” in 2017IEEE International Conference on Robotics and Automation (ICRA), May2017, pp 4885-4890; Wehbe, “Learning Coupled Dynamics Models ofUnderwater Vehicles Using Support Vector Regression,” in Oceans 2017,Aberdeen, June 2017; and Wu, “Parametric Identification and StructureSearching for Underwater Vehicle Model Using Symbolic Regression,”Journal of Marine Science and Technology, vol. 22, no. 1 pp. 51-60,2017; each of which is incorporated herein by reference.

b) neural network methods: for example as described in Vandeven,“Neutral Network Augmented Identification of Underwater Vehicle Models,”Control Engineering Practice vol. 15, no. 6, pp 715-725, 2007, specialsection on control application in marine systems; and Karras, “OnlineIdentification of Autonomous Underwater Vehicles through GlobalDerivative Free Optimization,” 2013 IEEE/RSJ International Conference onIntelligent Robots and Systems, November 2013, pp 3859-3864; each ofwhich is incorporated herein by reference.

Each of these above methods may be used with the present inventionregardless of the type of vehicle. As is well known to those of skill inthe art, the equations can be rewritten to account for the vehicle typeand the nomenclature/symbology normally used in the associated field.According to one embodiment of the invention, vehicle 100 control lawsinclude adaptive plant methods model 2700 as illustrated in the blockdiagram of FIG. 19 and as defined below. Vehicle 100 executes thesedynamic stability and control laws to control the motions and tonavigate vehicle 100.

$\begin{matrix}{\underset{\underset{{Inertial}{{Terms}.}}{︸}}{M\overset{.}{v}} = {{- \underset{\underset{{Coriolos}{Terms}}{︸}}{C\left( {M,v} \right)v}} - \underset{\underset{{Quadratic}{Drag}{Terms}}{︸}}{\left( {\sum\limits_{i = 1}^{6}{{❘v_{i}❘}D_{i}}} \right)v} - \underset{\underset{{Buoyancy}{Terms}}{︸}}{\mathcal{G}(a)} + {\underset{\underset{{Control}{{Forces}/{Moments}}}{︸}}{\tau\left( {v,a,\xi,\theta_{a}} \right)}.}}} & (1)\end{matrix}$

Where:

-   -   v ∈        ⁶ is the body velocity.    -   a is the body attitude vector.    -   M ∈        ^(6×6) is the positive definite symmetric mass matrix.    -   a D_(i) ∈        ^(6×6), i=(1, 2, . . . 6) is the negative semidefinite drag        matrix for the i^(th) degree of freedom    -   ξ ∈        ^(p) are control inputs such as fin angle and propeller speed.    -   θ_(a) ∈        ^(q) is vector of actuator parameters to be identified. Examples        of these terms include lift and drag coefficients of the control        surfaces and propeller coefficients

2.3.2 Center of Mass Redistribution Module

There may exist configurations of vehicle 100 for which the availablecontrol surfaces lack sufficient authority to reliably control thevehicle, or in which the vehicle is dynamically or statically unstableto such a degree as to make mission execution a concern. Alternatively,the initial vehicle 100 configuration may be within desired operatingenvelopes, but after dropping a cargo, collecting a sample, or droppingballast, the resulting vehicle 100 properties exceed safe operatingparameters. In such situations, relocating the center of mass/gravity ofvehicle 100 may sufficiently alter vehicle 100 stability and controlcharacteristics to return vehicle 100 to safe limits of operation.

FIG. 20A is a side cross sectional view and FIG. 20B is a second crosssectional view of a mass redistribution and configuration module 2750according to an embodiment of the invention. As shown in FIGS. 20A and20B, mass redistribution module 2750 includes mechanisms that canselectively change the location of vehicle 100 center of mass byrepositioning moveable masses on each of the vehicle's x, y, and z axes.In alternative embodiments of the invention, module 2750 includesmoveable masses for just a single one of the x, y, or z axes, or simplyany two of the x, y, or z axes. Optionally, for greater precision,module 2750 can include multiple moveable masses of different weights onany given one or more of these axes.

As shown in FIG. 20A, module 2750 includes a servo or DC drive motor2752, mounted on a motor mount or isolation plate 2754. Motor 2752drives a worm gear 2756 to which is attached a mass m, 2758. The wormgear is anchored to a termination plate 2760 secured to the module 2750structure either directly or through an isolation plate 2762. As shownin FIG. 20A, worm gear 2756 is located parallel to or on the x axis ofvehicle 100. Motor 2752 receives commands from vehicle 100 command logicvia data buses 106 and 107, to turn worm gear 2756 and position orreposition mass 2758 at the desired location along the x axis. Module2750 may optionally include a separate sensor to detect the position ofmass 2758; or optionally, module 2750 may be precalibrated to correlatethe number of revolutions of worm gear 2756 to a given location of mass2758.

FIG. 20B shows an end view of the module 2750 of FIG. 20A. In the crosssection of FIG. 20B, DC motor 2752 is coupled via additional gearing todrive a second worm gear 2764. Optionally, a second DC motor 2752 can beincluded to drive worm gear 2764. Motor 2752 receives commands fromvehicle 100 control logic to turn worm gear 2764 and position a mass2766 along or parallel to the vehicle 100 z axis. The position of mass2766 can be determined in a manner similar to that described inconnection with mass 2758.

Also shown in the embodiment of FIG. 20B is a third worm gear 2768coupled to a DC motor 2769. Motor 2769 turns worm gear 2768 in responseto commands received from the vehicle 100 control logic. Turning wormgear 2768 positions mass 2770 along the y axis of vehicle 100. Theposition of mass 2770 can be determined in a manner similar to thatdescribed in connection with the movements of masses 2758 and 2766.

Inclusion of module 2750 in the configuration and assembly of vehicle100 allows the vehicle 100 center of mass/gravity to be repositioned toobtain optimum performance of vehicle 100 and to maintain vehicle 100operating characteristics within desired operational envelopes. Any ofmasses 2758, 2766 or 2770 can be positioned or repositioned at any timeduring operation of vehicle 100. This capability additionally allowsvehicle 100 to be “trimmed” for the particular operating conditions ormanoeuvre. Trimming vehicle 100 reduces the amount of work the controlsurfaces must do to maintain vehicle 100 in a particular attitude ororientation. Reducing the number and magnitude of required motions ofthe control surfaces in turn saves vehicle power and increases vehicleendurance and range.

2.3.3 Buoyancy Control Module

Similar to the reasons for wanting to control the position of thevehicle 100 center of mass, when vehicle 100 comprises a UUV, theoperator may wish to provide a module for controlling the buoyancy ofvehicle 100. FIG. 21 illustrates a cross section of a buoyancy controlmodule 2775 according to an embodiment of the invention. Buoyancycontrol module 2775 selectively increases and decreases the net buoyancyof the vehicle 100. Module 2775 includes one or more flood tank areas2776 fluidly coupled to the exterior of the hull through port(s) 2778. Apiston 2780 is mounted on an actuator rod 2782 and coupled to DC servomotor 2784 through a gear box 2786. Servo motor 2784 moves piston 2780fore or aft inside flood chamber 2776 to increase or decrease flood tank2776 volume thereby changing the amount of water/fluid inside tank 2776.As the volume of water inside tank 2776 changes, the total buoyancy andthe center of buoyancy of vehicle 100 can be controlled and positioned.An air gap 2787 is provided where actuator rod 2782 enters flood chamber2776 to allow vehicle atmosphere to enter or leave the flood chamber aspiston 2780 is positioned and repositioned during use and to prevent thebuildup of a vacuum. Optionally, an airbladder (not shown) can beprovided for this purpose.

In operation, vehicle 2410 sends buoyancy correction commands via CANbus 106, 107 to module microprocessor 2788. Microprocessor 2788processes the received commands and issues reposition commands via CANbus 106, 107 to servo 2784 to reposition piston 2780 and alter theinterior volume of flood chamber 2776. As piston 2780 moves forward,water present in chamber 2776 is pushed out of opening 2778. As piston2780 moves back, more water enters the chamber 2776 through opening 2778to fill the expanding volume of the chamber 2776. Repositioning piston2780 in this manner thereby changes the vehicle buoyancy and also can beused to alter the location of the center of buoyancy. Vehicle 100 maycomprise multiple modules 2775 as appropriate to the vehicle'soperations and mission.

2.4 Telemetry and External Communications Systems

Once vehicle 100 commences autonomous operations, vehicle 100 cancommunicate with operators or with other vehicles via a communicationsmodem. Vehicle 100 modem can comprise radio communications, lightcommunications, or acoustic communications; or combinations thereof.Each of these modes of communication and the hardware for receiving andtransmitting said communications is well known to those of skill in theart. The particular choice of particular communication means isdependent in part on the intended vehicle use and operating environment.

2.4.1 Optical Communications Module

According to one embodiment of the invention, vehicle 100 includes anoptical communication module or element as shown in FIGS. 22A and 22B.FIG. 22A shows a front perspective view of optical communicationselement or module 2800 having a module body 2805 and a transparent frontdome 2810. Although shown in a nose cone configuration in FIGS. 22A and22B, optical module 2800 can be included anywhere in the vehicle 100modular or element configuration such as, for example, as illustrated inFIG. 22A. When constructed as a module, optical communications package2800 mates with the remainder of vehicle 100 using any of the connectorsof FIG. 5A-5F. When constructed as a configurable element, opticalcommunications package 2800 may be either moveable or fixed and matedwith vehicle 100 using any of the embodiments of FIG. 7-10 or 12 .

FIG. 22B shows module 2800 in cross section. On the interior oftransparent dome 2810 one or more lenses 2815 focus light onto aposition sensitive detector 2820. Transparent dome 2810 may comprise afilter material that transmits light of certain wavelengths whileexcluding or attenuating other wavelengths. Wavelengths of light mayinclude ultraviolet, infrared, and visible light. When vehicle 100comprises a UUV, green spectrum wavelengths have been shown to transmitinformation more robustly in an underwater environment. Lens 2815 canalso be designed to or coated to attenuate certain wavelengths whilepermitting other wavelengths to pass through to detector 2820.

Position sensitive detector 2820 may comprise a First Sensor DL 100-7model detector, the specification of which is incorporated herein byreference. Detector 2820 is mounted on a printed circuit board 2821which includes the module microprocessor. Circuit board 2821additionally includes additional processing and circuitry for processingdata received from and for issuing commands to other communicationsdevices such as RF or acoustic modems and communications when suchcircuits are also included within module 2800. As drawn in FIG. 22B,optical communications module 2800 includes an RF strip antenna 2822 forRF communications; and an acoustic modem 2823 for acousticcommunications. As with the optical communications, circuit board andprocessor 2821 routes communication to vehicle 100 central processor2410 via CAN bus 106, 107.

RF strip antenna 2822 can also be used for wireless communicationsbetween modules. Such communications may be desirable, for example, whena configurable element is attached to the exterior of vehicle 100. Theexternal configurable element, can transmit via wireless communicationits status, configuration, range of motion and other performanceparameters. Use of wireless communications avoids the need to provide awired bus connection between the element and the adjoining module toeffect communications with vehicle 100, and wherein such hard wiredconnections might penetrate the hull of vehicle 100. Even when vehicle100 comprises a UUV, the range over which the wireless radio frequenciesis so small such that attenuation should not be a concern. Optionally,rather than a single RF strip antenna 2822 located on communicationsmodule 2800, each module, or the command module could include a wirelessantenna to perform this function. Data received from any attachedconfigurable element could then be processed by the individual modulemicrocomputer. Optionally wireless configuration data can be shareddirectly with vehicle computer 2410 via buses 106, 107.

When light hits position sensitive detector 2820, detector 2820 outputis processed by circuit board electronics 2821 which transmits via CANbus 106, 107 a signal to vehicle command logic 2410. In this manner,transmitted light can be used for communications. For example, asequence of flashing lights can be transmitted from a source external tovehicle 100 and received by module 2800 as a coded message, for decodingby vehicle 100 command logic 2410.

In an alternative embodiment of the invention, the strength or locationof the centroid of the focused beam of light on detector 2820 relativeto the center of the detector is measured and communicated via databuses 106, 107 to vehicle control logic 2410. This information can beused by vehicle 100 to manage vehicle track relative to an externalilluminated target. If the external light is focused through lens 2815on the center of the detector, vehicle 100 is tracking to the target. Ifthe maximum energy of the external light is focused to be on other thanthe center of detector 2820, vehicle 100 is off course. Vehicle logic2410 can use this tracking information to issue propulsion or controlcommands to alter course as needed to track to the external illuminatedtarget.

According to another embodiment of the invention, optical module 2800may additionally include one or more of LEDs 2825, 2826, 2827. LEDs2825-2827 et seq. are located around the periphery of opticalcommunications module 2800 or positioned such that light emittedtherefrom does not interfere with light detected by detector 2820. TheLEDs may each be housed and protected within its own separatetransparent housing filled with engineering fluid. The engineeringfluid, as described previously above, provides for thermal managementand transfer of the heat generated by the LED to the exterior mediumoutside of the transparent housing. Each of LEDs 2825-2827 et seq. mayadditionally comprise an LED of a different wavelength, for example: oneblue, one green, one red, and so forth. The LEDs can be flashed in adifferent sequence of colors to communicate messages to the operator, aremote optical receiving modem, or to other vehicles. Various methods ofencoding messages using such techniques are known to those of skill inthe art.

2.4.2 Vehicle Swarm Communications

Optical communications modules 2800 may be used to coordinate movementsand activities among and between several vehicles. For example, theoperator might designate a “lead” vehicle for other vehicles to follow.In such a mode of operation, lead vehicle 100 might emit, for example ared encoded pulsing light from LED 2825 for vehicles on the port side oflead vehicle 100 to follow and a green encoded flashing light forvehicles on the starboard side to follow. In the configuration ofoptical module 2800 as shown, these light transmissions need only beseen by the receiving vehicle and that receiving vehicle need not bepointed directly at the light source. Detector 2820 can detect thewavelength of the received light and communicate that information backto vehicle command logic and central processing 2410. The encoded pulsescan include a sequence or data string that includes, for example, one ormore of: the vehicle ID, and indications of vehicle speed, course ordirection changes.

Optionally, communication module 2800 may include a Pixy Camera in lieuof or in addition to detector 2820. The complete specification of thePixy Camera is incorporated by reference. The Pixy camera can detect andseparate out as separate data streams, transmitted light of differentwavelengths. Thus, rather than receiving and acting upon communicationsreceived from just a single vehicle at a single wavelength, thereceiving vehicle 100 can have multiple simultaneous channels of visiblecommunication, each of a different wavelength. These multiple channelscan be from multiple adjacent vehicles, or from a single adjacentvehicle transmitting different types of data, each with its own channelof colored light.

FIG. 23 illustrates an example of vehicle 100 swami communications andcoordination. In FIG. 23 , a first vehicle 100 including an opticalcommunications module 2800 tracks towards and navigates to a flashingwhite light buoy 2850. A second vehicle 2852 follows vehicle 100 byreceiving transmitted green light pulses 2853 from vehicle 100. Vehicle2852 also executes mission instructions, such as for example, “stopfollowing,” received on a second channel of communication in yellowcolored light 2854 transmitted from vehicle 100. A third vehicle 2855located beneath vehicle 100 also tracks and follows vehicle 100 byreceiving red light pulses 2856 from vehicle 100. Vehicle 2855 can alsoreceive instructions from lead vehicle 100 via messages transmitted fromvehicle 100 via an LED emitting orange colored light; or optionally viaacoustical waves 2858 via acoustic modems included within itscommunications module 2800. Such instructions might include for example,“stop following and begin execution of mission profile #2.” Vehicle2855, may optionally transmit via LED light signal, acoustic modem, orradio frequency, a confirmation that commands from vehicle 100 have beenreceived. Vehicles 2852 can also relay instructions received fromvehicle 100 to vehicle 2855 on a separate communications channel 2860.Vehicles 2852 and 2855 can also communicate directly with each other, orwith other vehicles using LEDs or other available communicationschannels.

3.0 Example of Use

FIG. 24 is a flow chart illustrating possible use and operation of afield configurable vehicle according to an embodiment of the invention.FIGS. 25A and 25B shows the initial, 3000, and final vehicle 3001configuration resulting from the process described below and in the flowchart of FIG. 24 . In the fictitious example illustrated herein, theassembled vehicle comprises a UUV used on a scientific mission to samplegasses present in the ocean water near an off shore volcano.

In step 2900 of FIG. 24 , an operator identifies the mission objective,mission profile, and mission parameters for the UUV including neededsensors or other peripheral devices, for example grappling hooks orother attachable tools, desired to complete the mission. In thisexample, the operator decides that a gas sampling instrument andinfra-red sensor are needed to complete the test plan. The operatordetermines that a specialized pre-assembled module 3005 including thesetypes of sensors exists and selects that module as one of the modules tobe included in the final vehicle assembly.

The operator also identifies the distance to and method of transit tothe mission station; the vehicle's navigation equipment requirements:and whether the vehicle needs to maintain precise station keeping onarrival. In this example, the finally assembled vehicle will be deployedfrom a boat and then transit to a location near the volcano by attachingitself to the side of remote controlled undersea vehicle (ROV) using amagnetic attachment device. The vehicle operator notes that module 3005already includes a suitable attachment mechanism 3006 constructedaccording to the embodiment of FIG. 8 .

After hitching a ride to the vicinity of the underwater volcano, thefinally assembled UUV will detach itself and navigate and transit to thetest location via its own propulsion. The operator selects anappropriate propulsion module based on the time in transit and thedesired speed of transit as well as what type of search pattern orstation keeping the vehicle must maintain while collecting the datasamples. In this example, the vehicle will transit and then execute asearch grid while conducting the test. The operator thus selects apropulsion module 2199 with a fixed pitch propeller 2228 for thismission.

Once the sample collection is completed, the UUV will rise to thesurface for recovery. The operator thus selects a ballast module 3010with releasable ballast 1704 for this mission. The operator also selectsa command module 3015 and a battery module 3020 having sufficient powerto operate the UUV throughout the entire mission profile. The operatoralso selects moveable control elements such as stabilizers 3025, and bowplanes 3030; as well as fixed control surfaces such as a sail plane3035.

After selecting the needed configurable elements and the desiredmodules, in step 2910 of FIG. 24 , the operator assembles the modulestogether using the joining mechanisms previously described in connectionwith the embodiments of FIGS. 5A-5C. The operator can begin the assemblyprocess with any module, but in this example, the operator begins theassembly process with the battery module 3020 as the first module. Inthis manner, the electrical connections of any subsequently joinedmodules can be checked by noting if LED 511 illuminates on each module.LED 511 of any joined module can optionally also flash a code toindicate to the operator that the module has performed an internalself-check of its systems and is fully operational.

The operator next attaches command module 3015, on one end, and thepropulsion module 2199 on the other end of battery module 3020. In theembodiment of the invention as draw in FIG. 25 , the command module alsoincludes all the navigation systems for the vehicle. Optionally, aseparate navigation module, containing navigation systems such as, forexample but not limited to: six axis inertial navigation units (INU),GPS, other navigation systems can be installed.

In the configuration of FIG. 25A, the ballast module 3010 is attached tothe opposite end of command module 3015, followed by the sensor module3005 including the gas and infra-sensors, and attaches module 3005 inseries with the ballast module 3010. Sensor module 3005 additionallyincludes attachment device 3006: one of the mechanisms of FIGS. 8-11useful for attaching to the ROV that will ferry the finally assembledvehicle to the point of operation.

The operator then attaches the moveable and fixed controlsurfaces/elements to the exterior of the assembled vehicle. In thisexample, the operator also choses to attach a nose cone to the front ofthe vehicle. In this example the nose cone includes opticalcommunications package 2800. The initial vehicle assembly is shown inFIG. 25A.

With the initial vehicle components assembled, in step 2920, theoperator then uses top side controller 2470 to couple the initiallyassembled vehicle 3000 to topside computer 2530 and user interface 2600.The operator uses interface 2600 to verify vehicle system and componentstatus, and to load mission navigation, operating and performanceparameters into vehicle 3000's computer 2410 located in the vehicle'scommand module 3015. During this topside check of vehicle missionparameters and configuration, topside computer 2530 calculates that thecenter of mass location may be outside of allowable parameters once theballast module releases its ballast. Topside computer 2530 displays thisinformation to the operator via user interface 2600. The initialconfiguration of vehicle 3000 is therefore not acceptable and thevehicle must be reconfigured.

The operator then choses to separate the vehicle at the initial locationjoining the sensor 3005 and ballast 3010 modules; and inserts a module2750 with moveable internal weights as shown, for example, in FIG. 20 .Once ballast 1704 is released from ballast module 3010, command module3015 will execute instructions and reposition the internal weights 2758of module 2725 to maintain the center of gravity of the finallyassembled vehicle 3001 within allowable limits. The completely assembledvehicle 3001 is shown in FIG. 25B.

The operator once again checks the modules, elements, and overallconfiguration of vehicle 3001 and confirms that elements and modules areworking, mission navigation and operational parameters are correctlyloaded, and that vehicle 3001 can operate within allowable limits. Oncevehicle 3001 systems have been checked and mission parameters loaded,vehicle 3001 is decoupled from topside computer 2530 in step 2930 andreleased into the water. Vehicle 3001 computes its initial control lawsand stability coefficients from data received from the modules andattached elements, or as entered by the operator. Once in the water, instep 2940, vehicle 3001 then executes a series of manoeuvres andcollects data that measures changes in position, pitch, yaw and rollbased on control surface movements and compares that empirical data tothe computed and predicted result. Vehicle 3001 can then use filteringor averaging to further refine the calculated and empirically determinedstability and control coefficients.

Once systems checks and control parameters are complete, vehicle 3001embarks on its mission. In step 2950, vehicle 3001 tracks towards aflashing light emitted by the remotely piloted vehicle that will ferryvehicle 3001 to the test site local. Once proximate the ROV, vehicle3001 magnetically attaches itself to the ROV, and the ROV with vehicle3001 attached, transits to the test area. When the vehicle navigationsystem detects that vehicle 3001 has reached the release point, computer2410 sends a signal to the magnetic attachment mechanism which releasesvehicle 3001 from the ROV shuttle vehicle. Vehicle 3001 then achievesneutral buoyancy according to the amount of ballast loaded and thesurrounding water density; and in step 2960 the vehicle command module3015 navigates vehicle 3001 to the precise test station and executes thetest collection mission in step 2970. Vehicle 3001 can optionallytransmit telemetry via an acoustic modem or other communications meansincluded within the communications packages of nose cone 2800 throughoutthe mission.

After completing the mission, vehicle 3001 navigates to its missiondefined pick up location using GPS or internal navigation, or otherincluded navigation capabilities; and commands the release of ballast1704 and rises to the surface, in step 2980, according to itspreprogrammed mission profile. Once on the surface, vehicle 3001transmits a series of colored light pulses indicating statusinformation, such as for example: that it has completed its mission,that the vehicle is in good condition. Vehicle 3001 also transmits viaRF data indicating that it can be retrieved, and its location asdetermined by vehicle 3001 onboard navigation. The vehicle operator cantransmit a reply from the research ship acknowledging the message andcan optically, acoustically, or via RF communications transmit tovehicle 3001 other commands. Such commands might include instructionsfor vehicle 3001 to continue outputting a single flashing white light sothat it can be visually located, but to cease other transmissions. Theresearch vessel proceeds to the location and retrieves vehicle 3001.

In step 2995, vehicle 3001 is reconnected to topside computer 2530 anduser interface 2600. Prior to execution of step 2995, the operator canalso check any optional vehicle anti-tamper devices or security systemsto ensure that no unauthorized access to vehicle 3001 has occurred; andthat could also damage or inject malicious code into topside computer2530. Once coupled to topside computer 2530, the operator downloads thecollected data if not previously transmitted from vehicle 3001; andverifies vehicle 3001 component health and status. In step 2998, theoperator can disassemble vehicle 3001 and store its configurableelements and component modules for later use to configure a new vehicleat a later time.

What is claimed is:
 1. A method for providing propulsion to a vehicle,comprising the steps of: locating a first diametrically magnetizedmagnet having both a first polarity and an opposite polarity in aninterior volume of a propulsion module; locating a second diametricallymagnetized magnet having both the first polarity and the oppositepolarity in a propeller assembly, the first and second diametricallymagnetized magnets attract when the magnets are stationary; coupling apropeller to the second magnet; rotating the first magnet; and, rotatingthe second magnet in response to the rotation of the first magnetwhereby the propeller rotates.
 2. The method of claim 1, wherein thestep of rotating the first magnet further comprises coupling the firstdiametrically magnetized magnet to a dc motor.
 3. The method of claim 1,wherein the step of coupling the propeller to the second magnet furthercomprises coupling a counter rotating propeller.
 4. The method of claim1, wherein the step of locating the first magnet further comprisesproviding an air gap between an exterior wall of the propulsion moduleand the first magnet.
 5. The method of claim 1, wherein the step oflocating the second magnet further comprises providing an air gapbetween an exterior wall of the propeller assembly and the secondmagnet.
 6. The method of claim 1, wherein the propeller is formed byadditive manufacturing.
 7. The method of claim 1, wherein the propulsionmodule is formed by additive manufacturing.